I've known about Vimperator and Pentadactyl since the research I did that led to me starting to use Vimium, but since FF isn't my primary browser I've never tried either. Very interesting to see my sister commenters saying that Vimium doesn't even come close to their functionality. I might have to check Vimperator out.

One nitpick about Vimium - I don't like that "f" is included in the default possible characters for link hints, given that "f" is the shortcut to display hints. I always have to go to the settings and take it out, so I know that I can always hit "f" again (instead of Esc) to remove the hints without fear of accidentally leaving the page if I decide I don't want navigate away yet.

But at least the option is there! For which I am thankful.

That said, Vimperator is far from perfect and sometimes buggy and I don't need all the features (like macros).