well, lots of others, of course, but those I use most frequently now:

MicroB (of course) (with FlashBlock and mplayer plug-in)
Canola2 (primarily for podcasts and feature movies)
FBReader (I *love* this program; can really read whole books)
emelfm2 and Xterm (for tinkering with the NIT)
Personal Menu
Gene Cash's Calend and To Do



and I expect to be using much more of:

Skype
Xournal
sdict
maemo recorder