Useful links: Best Mac Software | Open Source Mac

Chat

• Adium - chat client that uses libpurple (AIM, MSN, Yahoo, XMPP, etc..)
• Colloquy - IRC chat client

Desktop Improvements

• Quicksilver - utility software program for Mac OS X (application launcher, etc…)

Graphics

• Gimp - popular image editing software for OS X
• Pencil - animation/drawing software
• Seashore - simple image editing software based on GIMP

Media

• Senuti - transfer songs from your iPod to your computer
• VLC - media player

Network

• KisMac - wi-fi stumbler and cracker
• iStumbler - wi-fi stumbler
• MacroPolo - context-aware computing (change Network Location by SSID etc…)

Office

• NeoOffice - port of OpenOffice.org (doesn’t require X11)

Security

• GPGMail - PGP plugin for Mail.app
• MacGPG - GPG tools for the MAC
• Vidalia - TOR for OS X

Utilities

• Fink - apt-get for OS X
• KeyFixer - fix home and end keys
• KeyFixer Firefox - fix home and end keys in Firefox
• MacPorts - open source software (ports for OS X)
• Mozy - remote backup software
• VirtualBox - x86 virtualization (run Linux, Windows, FreeBSD, etc…)

Web Browsing / News

• Firefox - web browser
• Vienna - news reader