diff --git a/pages/settings.mako b/pages/settings.mako
index b9fd47b..2834838 100644
--- a/pages/settings.mako
+++ b/pages/settings.mako
@@ -69,7 +69,7 @@
             <h2>Cookies</h2>
             % if cookies:
                 <table>
-                <% cookie_order = ["EarwigDefaultProject", "EarwigDefaultLang", "EarwigBackground", "EarwigCVShowDetails", "EarwigBackgroundCache"] %>\
+                <% cookie_order = ["EarwigDefaultProject", "EarwigDefaultLang", "EarwigBackground", "EarwigScreenCache", "EarwigCVShowDetails"] %>\
                 % for key in [key for key in cookie_order if key in cookies]:
                     <% cookie = cookies[key] %>\
                     <tr>
diff --git a/pages/support/footer.mako b/pages/support/footer.mako
index 2caa50c..a8844f2 100644
--- a/pages/support/footer.mako
+++ b/pages/support/footer.mako
@@ -1,4 +1,5 @@
 <%page args="environ, cookies"/>\
+<%namespace module="toolserver.background" import="get_desc_url"/>\
 <%!
     from os import path
 %>\
@@ -19,7 +20,7 @@
                             <a href="mailto:earwig@toolserver.org">Contact</a> &bull; \
                             <a href="https://github.com/earwig/toolserver">View Source</a> &bull; \
                             % if ("EarwigBackground" in cookies and cookies["EarwigBackground"].value in ["potd", "list"]) or "EarwigBackground" not in cookies:
-                                <a id="bg_image_link" href="">Background</a> &bull; \
+                                <a href="${get_desc_url() | h}">Background</a> &bull; \
                             % endif
                             <a href="http://validator.w3.org/check?uri=referer">Valid XHTML 1.0 Strict</a>
                         </p>
diff --git a/pages/support/header.mako b/pages/support/header.mako
index dd981e5..846e72e 100644
--- a/pages/support/header.mako
+++ b/pages/support/header.mako
@@ -1,4 +1,5 @@
 <%page args="environ, cookies, title, slug=None, add_css=(), add_js=()"/>\
+<%namespace module="toolserver.background" import="set_background"/>\
 <%namespace name="index" file="/index.mako" import="get_tools"/>\
 <%!
     from os import path
@@ -31,10 +32,9 @@
     <% selected = cookies["EarwigBackground"].value if "EarwigBackground" in cookies else "list" %>\
     % if selected in ["plain-brown", "plain-blue"]:
         <body style="background-image: url('${root}/static/images/background-${selected[6:]}.png');">
-    % elif selected == "potd":
-        <body onload="set_background_potd()" style="background-repeat: no-repeat;">
     % else:
-        <body onload="set_background_list()" style="background-repeat: no-repeat;">
+        <% bg_url = set_background(cookies, selected) %>\
+        <body onload="update_screen_size()" style="background-image: url('${bg_url | h}'); background-size: cover;">
     % endif
         <div id="header">
             <p id="heading"><a class="dark" href="${pretty}">earwig</a><span class="light">@</span><a class="mid" href="https://wiki.toolserver.org/">toolserver</a><span class="light">:</span><a class="dark" href="${this}">${slug}</a></p>
diff --git a/schema.sql b/schema.sql
index cd1c3bf..cd4ade1 100644
--- a/schema.sql
+++ b/schema.sql
@@ -10,6 +10,21 @@ CREATE DATABASE `u_earwig_toolserver`
   DEFAULT COLLATE utf8_unicode_ci;
 
 --
+-- Table structure for table `background`
+--
+
+DROP TABLE IF EXISTS `background`;
+CREATE TABLE `background` (
+  `background_id` int(9) unsigned NOT NULL,
+  `background_filename` varchar(512) COLLATE utf8_unicode_ci DEFAULT NULL,
+  `background_url` varchar(512) COLLATE utf8_unicode_ci DEFAULT NULL,
+  `background_descurl` varchar(512) COLLATE utf8_unicode_ci DEFAULT NULL,
+  `background_width` int(9) unsigned DEFAULT NULL,
+  `background_height` int(9) unsigned DEFAULT NULL,
+  PRIMARY KEY (`background_id`)
+) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci;
+
+--
 -- Table structure for table `language`
 --
 
diff --git a/static/js/copyvios.js b/static/js/copyvios.js
index 1568b4c..0560669 100644
--- a/static/js/copyvios.js
+++ b/static/js/copyvios.js
@@ -5,7 +5,7 @@ function copyvio_toggle_details(details) {
     if (link.innerHTML == "Show details:") {
         details.style.display = "block";
         link.innerHTML = "Hide details:";
-        set_cookie("EarwigCVShowDetails", "True", 365);
+        set_cookie("EarwigCVShowDetails", "True", 1095);
     } else {
         details.style.display = "none";
         link.innerHTML = "Show details:";
diff --git a/static/js/potd.js b/static/js/potd.js
index 7db5558..520d0cc 100644
--- a/static/js/potd.js
+++ b/static/js/potd.js
@@ -1,181 +1,26 @@
-function set_background_potd() {
-    if (cache_cookie()) return;
-    var d = new Date();
-    var callback = "earwigpotd1";
-    var date = (d.getUTCFullYear()) + "-" + zero_pad(d.getUTCMonth() + 1, 2) + "-" + zero_pad(d.getUTCDate(), 2);
-    var base = "//commons.wikimedia.org/w/api.php?action=query&prop=revisions&rvprop=content&format=json&titles=Template:Potd/";
-    var url = base + date + "&callback=" + callback;
-
-    var script = document.createElement("script");
-    var head = document.getElementsByTagName("head")[0];
-
-    window[callback] = function(data) {
-        head.removeChild(script);
-        parse_potd_file_name(data);
-    };
-
-    script.src = url;
-    head.appendChild(script);
-}
-
-function set_background_list() {
-    if (cache_cookie()) return;
-    var callback = "earwigpotd1";
-    var base = "//commons.wikimedia.org/w/api.php?action=query&prop=revisions&rvprop=content&format=json&titles=User:The+Earwig/POTD";
-    var url = base + "&callback=" + callback;
-
-    var script = document.createElement("script");
-    var head = document.getElementsByTagName("head")[0];
-
-    window[callback] = function(data) {
-        head.removeChild(script);
-        parse_list_file_name(data);
-    };
-
-    script.src = url;
-    head.appendChild(script);
+function update_screen_size() {
+    var cache = cache_cookie();
+    var data = {
+        "width": window.screen.availWidth,
+        "height": window.screen.availHeight
+    }
+    if (!cookie || cookie["width"] != data["width"] || cookie["height"] != data["height"]) {
+        set_cookie("EarwigScreenCache", JSON.stringify(data), 1095);
+    }
 }
 
 function cache_cookie() {
-    var cookie = get_cookie("EarwigBackgroundCache");
+    var cookie = get_cookie("EarwigScreenCache");
     if (cookie) {
         try {
             data = JSON.parse(cookie);
-            var filename = data.filename;
-            var url = data.url;
-            var descurl = data.descurl;
-            var imgwidth = data.imgwidth;
-            var imgheight = data.imgheight;
-            if (filename && url && descurl && imgwidth && imgheight) {
-                set_background(filename, url, descurl, imgwidth, imgheight);
-                return true;
+            var width = data.width;
+            var height = data.height;
+            if (width && height) {
+                return {"width": width, "height": height};
             }
         }
         catch (SyntaxError) {}
     }
     return false;
 }
-
-function parse_potd_file_name(data) {
-    var content = "";
-    var res = data["query"]["pages"];
-    for (pageid in res) {
-        content = res[pageid]["revisions"][0]["*"];
-    }
-    var filename = /\{\{Potd filename\|(1=)?(.*?)\|.*?\}\}/.exec(content)[2];
-
-    var callback = "earwigpotd2";
-    var base = "//commons.wikimedia.org/w/api.php?action=query&prop=imageinfo&iiprop=url|size&format=json&titles=File:";
-    var url = base + escape(filename) + "&callback=" + callback;
-
-    var script = document.createElement("script");
-    var head = document.getElementsByTagName("head")[0];
-
-    window[callback] = function(data) {
-        head.removeChild(script);
-        parse_file_url(data, escape(filename.replace(/ /g, "_")));
-    };
-
-    script.src = url;
-    head.appendChild(script);
-}
-
-function parse_list_file_name(data) {
-    var content = "";
-    var res = data["query"]["pages"];
-    for (pageid in res) {
-        content = res[pageid]["revisions"][0]["*"];
-    }
-
-    var filenames = [];
-    var regexp = /\*\*?\s*\[\[:File:(.*?)\]\]/g;
-    while ((match = regexp.exec(content)) !== null) {
-        filenames.push(match[1]);
-    }
-    var filename = filenames[Math.floor(Math.random() * filenames.length)];
-
-    var callback = "earwigpotd2";
-    var base = "//commons.wikimedia.org/w/api.php?action=query&prop=imageinfo&iiprop=url|size&format=json&titles=File:";
-    var url = base + escape(filename) + "&callback=" + callback;
-
-    var script = document.createElement("script");
-    var head = document.getElementsByTagName("head")[0];
-
-    window[callback] = function(data) {
-        head.removeChild(script);
-        parse_file_url(data, escape(filename.replace(/ /g, "_")));
-    };
-
-    script.src = url;
-    head.appendChild(script);
-}
-
-function parse_file_url(data, filename) {
-    var url = "";
-    var descurl = "";
-    var imgwidth = 1024;
-    var imgheight = 768;
-
-    var res = data["query"]["pages"];
-    for (pageid in res) {
-        r = res[pageid]["imageinfo"][0];
-        url = r["url"];
-        descurl = r["descriptionurl"];
-        imgwidth = r["width"];
-        imgheight = r["height"];
-    }
-
-    set_background(filename, url, descurl, imgwidth, imgheight);
-    var data = {"filename": filename, "url": url, "descurl": descurl, "imgwidth": imgwidth, "imgheight": imgheight};
-    var expires = new Date();
-    expires.setUTCMilliseconds(0);
-    expires.setUTCSeconds(0);
-    expires.setUTCMinutes(0);
-    expires.setUTCHours(0);
-    expires.setUTCDate(expires.getUTCDate() + 1);
-    set_cookie_with_date("EarwigBackgroundCache", JSON.stringify(data), expires);
-}
-
-function set_background(filename, url, descurl, imgwidth, imgheight) {
-    var s = get_window_size();
-    var winwidth = s[0];
-    var winheight = s[1];
-
-    var width = winwidth;
-    if (imgwidth/imgheight > winwidth/winheight) {
-        width = Math.round((imgwidth/imgheight) * winheight);
-    }
-    if (width >= imgwidth) {
-        document.body.style.backgroundImage = "url('" + url + "')";
-        if (width > imgwidth) {
-            document.body.style.setProperty("background-size", "cover");
-        }
-    } else {
-        url = url.replace(/\/commons\//, "/commons/thumb/") + "/" + width + "px-" + filename;
-        document.body.style.backgroundImage = "url('" + url + "')";
-    }
-    document.getElementById("bg_image_link").href = descurl;
-}
-
-function zero_pad(value, length) {
-    value = String(value);
-	length = length || 2;
-	while (value.length < length) {
-	    value = "0" + value;
-    }
-	return value;
-}
-
-function get_window_size() {
-    // See http://www.javascripter.net/faq/browserw.htm
-    if (document.body && document.body.offsetWidth && document.body.offsetHeight) {
-        return [document.body.offsetWidth, document.body.offsetHeight];
-    }
-    if (document.compatMode=="CSS1Compat" && document.documentElement && document.documentElement.offsetWidth && document.documentElement.offsetHeight) {
-        return [document.documentElement.offsetWidth, document.documentElement.offsetHeight];
-    }
-    if (window.innerWidth && window.innerHeight) {
-        return [window.innerWidth, window.innerHeight];
-    }
-    return [1024, 768];
-}
diff --git a/toolserver/background.py b/toolserver/background.py
new file mode 100644
index 0000000..6f950eb
--- /dev/null
+++ b/toolserver/background.py
@@ -0,0 +1,115 @@
+# -*- coding: utf-8  -*-
+
+from datetime import datetime, timedelta
+from json import loads
+import random
+import re
+from time import time
+
+from earwigbot import exceptions
+
+from .misc import get_bot, open_sql_connection
+
+_descurl = None
+
+def set_background(cookies, selected):
+    global _descurl
+    conn = open_sql_connection(get_bot(), "globals")
+    if "EarwigScreenCache" in cookies:
+        cache = cookies["EarwigScreenCache"].value
+        try:
+            screen = loads(cache)
+            int(screen["width"])
+            int(screen["height"])
+        except (ValueError, KeyError):
+            screen = {"width": 1024, "height": 768}
+    else:
+        screen = {"width": 1024, "height": 768}
+
+    if selected == "potd":
+        info = _update_url(conn, "background_potd", 1, _get_fresh_potd)
+    else:
+        info = _update_url(conn, "background_list", 2, _get_fresh_list)
+    filename, url, descurl, width, height = info
+    bg_url = _build_url(screen, filename, url, width, height)
+    _descurl = descurl
+    return bg_url
+
+def get_desc_url():
+    return _descurl
+
+def _update_url(conn, service, bg_id, callback):
+    query1 = "SELECT update_time FROM updates WHERE update_service = ?"
+    query2 = "SELECT 1 FROM background WHERE background_id = ?"
+    query3 = "DELETE FROM background WHERE background_id = ?"
+    query4 = "INSERT INTO background VALUES (?, ?, ?, ?, ?, ?)"
+    query5 = "SELECT 1 FROM updates WHERE update_service = ?"
+    query6 = "UPDATE updates SET update_time = ? WHERE update_service = ?"
+    query7 = "INSERT INTO updates VALUES (?, ?)"
+    query8 = "SELECT * FROM background WHERE background_id = ?"
+    with conn.cursor() as cursor:
+        cursor.execute(query1, (service,))
+        try:
+            update_time = datetime.utcfromtimestamp(cursor.fetchall()[0][0])
+        except IndexError:
+            update_time = datetime.min
+        plus_one = update_time + timedelta(days=1)
+        max_age = datetime(plus_one.year, plus_one.month, plus_one.day)
+        if datetime.utcnow() > max_age:
+            filename, url, descurl, width, height = callback()
+            cursor.execute(query2, (bg_id,))
+            if cursor.fetchall():
+                cursor.execute(query3, (bg_id,))
+            cursor.execute(query4, (bg_id, filename, url, descurl, width,
+                                    height))
+            cursor.execute(query5, (service,))
+            if cursor.fetchall():
+                cursor.execute(query6, (time(), service))
+            else:
+                cursor.execute(query7, (service, time()))
+        else:
+            cursor.execute(query8, (bg_id,))
+            filename, url, descurl, width, height = cursor.fetchone()[1:]
+    return filename, url, descurl, width, height
+
+def _get_fresh_potd():
+    site = _get_site()
+    date = datetime.utcnow().strftime("%Y-%m-%d")
+    page = site.get_page("Template:Potd/" + date)
+    regex = ur"\{\{Potd filename\|(?:1=)?(.*?)\|.*?\}\}"
+    filename = re.search(regex, page.get()).group(1)
+    return _load_file(site, filename)
+
+def _get_fresh_list():
+    site = _get_site()
+    page = site.get_page("User:The Earwig/POTD")
+    regex = ur"\*\*?\s*\[\[:File:(.*?)\]\]"
+    filenames = re.findall(regex, page.get())
+    filename = random.choice(filenames)
+    return _load_file(site, filename)
+
+def _load_file(site, filename):
+    res = site.api_query(action="query", prop="imageinfo", iiprop="url|size",
+                         titles="File:" + filename)
+    data = res["query"]["pages"].values()[0]["imageinfo"][0]
+    url = data["url"]
+    descurl = data["descriptionurl"]
+    width = data["width"]
+    height = data["height"]
+    return filename.replace(" ", "_"), url, descurl, width, height
+
+def _get_site():
+    bot = get_bot()
+    try:
+        return bot.wiki.get_site("commonswiki")
+    except exceptions.SiteNotFoundError:
+        return bot.wiki.add_site(project="wikimedia", lang="commons")
+
+def _build_url(screen, filename, url, imgwidth, imgheight):
+    width = screen["width"]
+    if float(imgwidth) / imgheight > float(screen["width"]) / screen["height"]:
+        width = int(float(imgwidth) / imgheight * screen["width"])
+    if width >= imgwidth:
+        return url
+    url = url.replace("/commons/", "/commons/thumb/")
+    return url + "/" + width + "px-" + filename
diff --git a/toolserver/misc.py b/toolserver/misc.py
index d65903f..b115131 100644
--- a/toolserver/misc.py
+++ b/toolserver/misc.py
@@ -6,6 +6,9 @@ from urlparse import parse_qs
 from earwigbot.bot import Bot
 import oursql
 
+_bot = None
+_connections = {}
+
 class Query(object):
     def __init__(self, environ, method="GET"):
         self.query = {}
@@ -35,7 +38,15 @@ class Query(object):
             self.query[key] = value
 
 
+def get_bot():
+    global _bot
+    if not _bot:
+        _bot = Bot(".earwigbot", 100)  # Don't print any logs to the console
+    return _bot
+
 def open_sql_connection(bot, dbname):
+    if dbname in _connections:
+        return _connections[dbname]
     conn_args = bot.config.wiki["_toolserverSQL"][dbname]
     if "read_default_file" not in conn_args and "user" not in conn_args and "passwd" not in conn_args:
         conn_args["read_default_file"] = expanduser("~/.my.cnf")
@@ -43,7 +54,9 @@ def open_sql_connection(bot, dbname):
         conn_args["autoping"] = True
     if "autoreconnect" not in conn_args:
         conn_args["autoreconnect"] = True
-    return oursql.connect(**conn_args)
+    conn = oursql.connect(**conn_args)
+    _connections[dbname] = conn
+    return conn
 
 def urlstrip(context, url):
     if url.startswith("http://"):
@@ -55,6 +68,3 @@ def urlstrip(context, url):
     if url.endswith("/"):
         url = url[:-1]
     return url
-
-def get_bot():
-    return Bot(".earwigbot", 100)  # Don't print any logs to the console
diff --git a/toolserver/settings.py b/toolserver/settings.py
index 08b49c4..cf0a791 100644
--- a/toolserver/settings.py
+++ b/toolserver/settings.py
@@ -25,17 +25,17 @@ def _do_set(query, headers, cookies):
     if query.lang:
         key = "EarwigDefaultLang"
         if key not in cookies or cookies[key].value != query.lang:
-            set_cookie(headers, cookies, key, query.lang, 365)
+            set_cookie(headers, cookies, key, query.lang, 1095)
             changes.add("site")
     if query.project:
         key = "EarwigDefaultProject"
         if key not in cookies or cookies[key].value != query.project:
-            set_cookie(headers, cookies, key, query.project, 365)
+            set_cookie(headers, cookies, key, query.project, 1095)
             changes.add("site")
     if query.background:
         key = "EarwigBackground"
         if key not in cookies or cookies[key].value != query.background:
-            set_cookie(headers, cookies, key, query.background, 365)
+            set_cookie(headers, cookies, key, query.background, 1095)
             delete_cookie(headers, cookies, "EarwigBackgroundCache")
             changes.add("background")
     if changes:
