Vimperator!!!! Great, great, great Firefox add-on which, through its robust keyboard-driven, command-line interface, has dramatically improved my workflow. I started compiling a list of several default mappings and custom commands that I have been using again and again.
I use Vimperator in combination with Tree-Style Tabs, and have removed all of Firefox’s native GUI in the process. What remained felt a bit uncomfortable at first (no URL bar?), yet the ease at which I was able to command the browser won me over fairly quickly. Breaking the Mouse-paradigm is a great feeling, and without the clutter of toolbars/status bars/bookmark bars, you get a very different sense while browsing; a visceral browsing experience — one that appealed to me.
One of the downsides is that I have noticed Vimperator struggling when there are a large number of tabs open (over 15-20), or on certain pages. So far, this hasn’t been much of a deterrent. 😉
Some Vimperator-related resources: