Software written by people other than Apple or you (and if you're releasing it for others, even by you!).

• AbiWord -- word processor (Unix GUI)
• GnuMeric -- spreadsheet (Unix GUI)
• MagicPoint -- presentation (Unix GUI to present, command line to create)
• OroborOSX -- One of many Unix WindowManagers; tailored for OS X
• XDarwin -- Unix window server

Note: XDarwin and at least one of the WindowManagers is required for Unix GUI software

1 Browsers

• ChimeraBrowser -- Small/fast Gecko-based web browser
• SafariBrowser

2 Utilities

• YourIPis
• Visage -- login text and image customizations
• TinkerTool -- enable many hidden options
• SuitCase -- manage sets of fonts
• NiftyTelnet
• MacJanitor -- run Apple's maintenance scripts (which may not run otherwise)
• FruitMenu -- customize the Apple menu
• FontReserve -- organize your fonts
• ClassicSpy -- monitor/toggle Classic
• CarbonCopyCloner -- make bootable copies of disks

3 Internet

• AthenaIRC

Unix-related stuff:

• ManThor -- graphical interface for shell commands
• BashShell -- popular alternative to tcsh (the included shell)
• Pseudo - run software as root
• OSXDiskQuota
• DesktopConsole -- put your console on the desktop
• MacGrep

To be categorized:

• SharePoints
• RamBunctious
• PrintCenterRepair
• Passenger
• DigiTunnel

My thought is to provide a richer index to such software than the Category that already exists. --JohnAbbe

See CategoryThirdParty for a current, unannotated list.