Hey all,
I really like:
All-in-One Gestures 0.12.4. It's one of the "standard" downloads from the firefox extensions page. "This extension allows you to execute common commands using mouse gestures, rocker navigation, scroll wheel navigation and page scrolling."
In a nut shell, you hold down the left mouse button, and then move the mouse about an inch or so in a defined direction/pattern (from simple to ELABORATE) and it executes a command. Having it set to forward and back saves a lot of time when surfing feverishly. I found that my favorite setup is:
Left: Back
Right: Forward
Up: New Window
Down: Reload
Hope this helps,
Matt!