Greasemonkey is a firefox extension that allows you to customize the way a webpage displays using small bits of JavaScript You can download the extension here ; https://addons.mozilla.org/nl/firefox/addon/748 For scripts goto http://userscripts.org/

One of the first things I install after I install firefox. This is a great firefox extension ! Install Xmarks on each computer you use, and it seamlessly integrates with your web browser and keeps your bookmarks safely backed up and in sync. http://www.xmarks.com