At our company we use Debian Linux for most servers, Redhat on a few. Though I absolutely love Linux, recently we got a new line of server to do test products on and I have been playing with FreeBSD's JAIL environment.
For the most part JAIL is relatively new, however, it's features are unparalleled. Last night I managed to configure Frontpage 2002 extensions with the various security wrappers in a manner which works with our control panel (written in php!) -- the only "uncool" part was patching suexec -- unhappy with that, though security level hasn't been effected. People running BSD probably have all kinds of ogod things to say about JAIL, I hope to be one of them soon.
I run debian linux as my desktop with a win-xp partition (... easy now.... it's just for counter-strike...).
It's 9:23 p.m, I am alone in the office making coffee. I was trashed today by Crafty (the chess program) 4 times in 30 minutes. I deleted it.
-m.