There are 2 previous versions of this script.
// ==UserScript==
// @name Add Links to Google Bar
// @version 1.0
// @namespace http://nitinjain.info
// @description Adds new links to the Google Bar
// @license GPL v2
// @grant none
// @include https://*.google.com/*
// @include http://*.google.com/*
// ==/UserScript==
var googlebar = document.getElementById('gbz').getElementsByClassName('gbtc')[0];
var newLinks =[];
// Add your links here..
newLinks.push({name: 'Facebook', href: 'http://www.facebook.com'});
newLinks.push({name: 'Yahoo', href: 'http://www.yahoo.com'});
newLinks.push({name: 'Bing', href: 'http://www.bing.com'});
for (var i = 0; i < newLinks.length; i++) {
var newli = document.createElement('li');
newli.setAttribute('class', 'gbt');
googlebar.appendChild(newli);
var newlink = document.createElement('a');
newlink.setAttribute('href', newLinks[i].href);
newlink.setAttribute('class', 'gbzt');
newli.appendChild(newlink);
var span1 = document.createElement('span');
span1.setAttribute('class', 'gbtb2');
newlink.appendChild(span1);
var textlink = document.createElement('span');
textlink.setAttribute('class', 'gbts');
textlink.innerHTML = newLinks[i].name;
newlink.appendChild(textlink);
}