Using Greasemonkey:

• To install Greasemonkey scripts when you only have the source, save the code as a .user.js file, and choose file-open in Firefox.

• GreaseMonkey Script for eventid.net - when using eventid.net if you're not a subscriber, the MS KB links don't work. This script fixes that.
• User Reader Subscribe Button - adds an icon to the top right of each page that has an RSS feed, and indicates whether or not you have already added it to Google Reader.

• Online book about creating Greasemonkey scripts: www.diveintogreasemonkey.org