http://meta.stackoverflow.com/q/228294/223030 - So! Much! Cheese! Moved!

oldfavicon.user.js

// ==UserScript==
// @name Old [M]SO Favicon
// @description For those who like their bars substantial.
// @namespace michaelb958
// @author michaelb958
// @license MIT (http://opensource.org/licenses/MIT)
// @include *://stackoverflow.com/*
// @include *://*.stackoverflow.com/*
// ==/UserScript==

function with_jQuery(f) {
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  s.type = "text/javascript";
  s.textContent = "(" + f.toString() + ")(jQuery)";
  s.setAttribute('data-with-jquery', '');
  document.head.appendChild(s);
};
 
with_jQuery(function($) {
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    // doesn't take effect immediately in Firefox
    .detach().appendTo(document.head);
});