Convert a search on a StackExchange site to a Google search of that site

ht-se-search-google.user.js

// ==UserScript==
// @name           Hippietrail's StackExchange search to Google search
// @description    Convert a search on a StackExchange site to a Google search of that site
// @version        0.0
// @namespace      hippietrail
// @include        http://stackoverflow.com/search*
// @include        http://meta.stackoverflow.com/search*
// @include        http://serverfault.com/search*
// @include        http://meta.serverfault.com/search*
// @include        http://superuser.com/search*
// @include        http://meta.superuser.com/search*
// @include        http://stackapps.com/search*
// @include        http://*.stackexchange.com/search*
// @include        http://meta.*.stackexchange.com/search*
// ==/UserScript==

function main() {
  $('#bigsearch tr:last td:first').removeProp('colspan')
    .parent().append('<td><input type="button" name="google" value="google"></td>');

  $('input[name=google]').click(function (event) {
    location.href =
      'http://google.com'
      + location.pathname
      + location.search + '+site:' + location.hostname;
  });
}

function addJsNode(func) {
  'use strict';

  var targ = document.getElementsByTagName('head')[0] || document.body || document.documentElement,
    scriptNode = document.createElement('script');

  scriptNode.type = 'text/javascript';

  scriptNode.textContent = '(' + func.toString() + ')()';

  targ.appendChild(scriptNode);
}

addJsNode(main);