Better Gmail (Firefox Extension)
Lifehacker released a Firefox extension that can make the use of Gmail even better. This extension provides several useful functions, like Saved Searches, Label Colors, Filter Assistant, Conversation Preview and Attachment Icons etc. If you already use GMail, you should try out this Better Gmail.
(04/20/07) I have started to use Better GMail extension with Label Colors on, which would few steps to get it working.
Further demonstration, Hack Attack: Supercharing GMail, which will “show you how to use Better Gmail along with a few other Gmail add-ons to turn Gmail into the best email application you’ve ever used.”