underdog, underrated, under the radar OS
This OS is awesome. It is the most secure and stable OS I have ever seen. It runs exceedingly well on ancient equipment, and installs in about ten minutes. No extra cruft. No kitchen sink. Just a nice tight BSD UNIX OS. Very killer firewall package (pf) built in.
Oh, BTW, 3.1 is out now and unfortunately was not announced here. I'm running it on a firewall with 10 ethernet adapters and it is just rock solid.
An open, cross-platform journaling program.
A scientific plotting package.