Termix is one of the best killer apps to come to the Linux platform. Nate Case is one of the best Linux software writers I know, and termix shows his fine craftsmanship through this perfectly-designed telnet client. Until now, there hasn't been any way for Linux users to enjoy the oldschool telnet BBS's that are now popping up on the internet. The default 'telnet' command sucks for ansi, and doesn't support z-modem. If you are a serious telnet user, termix is definately for you.
An open, cross-platform journaling program.
A scientific plotting package.