Mac OS X is built on UNIX, but it doesn’t ship with a lot of the classic applications and libraries ‘Nix users are used to under UNIX. If you find yourself missing some of your old friends check out UNIX Utilities for Mac OS X.
This collection of some of the most requested UNIX applications comes with everything you need to integrate them seemlessly into your Mac OS X desktop.
The Mac OS X terminal app that ships with OS X, but maybe you prefer ETerm, xterm, and rxvt — which may handle non-english fonts better or otherwise fit your needs a little better. Are you looking for Gimp for image processing, AbiWord for word processing, or xchat to talk to friends on an irc network? All these and more are included.
UNIX utilities for Mac OS X bridges the gap and unlocks the full power of UNIX under Mac OS X. It costs $29.95.
More info here.