Not free, but works on many platforms including BSD, Linux, Windows, and Solaris. It's licencing is per PERSON, per platform. You can run any licence on as many machines as you like, provided they are the same platform and you are only using one at a time.
Visual Slick Edit has all the faetures of a great editor, as well as an IDE. It has different precanned setups (Emacs emulation, vi emulation, MS emulation) as well as the ability to totally customize everything.
I highly recommend it!
"Nothing is sure but death and taxes" I say combine the two and its death to all taxes!