Firefox, Safari, and other great web development tools
Moleskin has, yet another, list of very useful webdevelopment extensions for firefox. I don't know how I lived without some of these extensions!
And, on the topic of web development, SafariTest is a great tool which lets you see how your web page would look in Safari (OSX). They've even got a public test server that you can login and use (via VNC) to test Safari.