The ioquake3 community effort to continue supporting/developing id's
Improved Quake III Arena engine
FVWM-Crystal aims to create an easy to use and powerful desktop.
Customizable Windows terminal with tabs, splits, quake-style, etc.
Local Terminal Emulator
Source port of Doom, Heretic, Hexen and Strife developed in Delphi
Quake-like Console Emulator
A QuakeWorld package containing everything needed to play QW right now
Free and open source FPS based on Quake III Arena