Mouse Gestures for Mozilla
Update: Mouse gestures...
OK, so am I the only one on the planet who didn't know about mouse gestures? Why didn't someone clue me in?
Sure, I've never used Opera, which is where mouse gestures were pioneered in a browser, and even if I had, Opera for Mac only has limited support. But now I find that I can use 'em in Netscape 7.0 (and most if not all versions of Mozilla), so I walk in the blindness of ignorance no longer.
If you claim to not know what mouse gestures are, in order to make me feel better, then humor me while I explain that they allow you to control your browser by making small movements with a clicked mouse. The movements are mapped in the following graphic, and they resemble nothing so much as Palm's Graffiti® PDA stylus movements.

Mouse gestures for Mozilla/Netscape are downloaded and installed as a plug-in...very painless. A panel in the browser preferences (advanced) lets you customize the mouse movements so as to minimize conflicts between gestures and other behavior (such as highlighting text). The preferences panel even comes with an uninstall button in case you decide gestures isn't your cup of tea.
I'm still in the early learning stages, using gestures primarily to move forward and backward in history, and to increase/decrease text size. Combine gestures with a wireless mouse and you have a situation that will potentially provide great relief for RMS-type ailments.
[Link tip to Simon Willison]
