A modern, cross-platform Quake game engine based on FitzQuake.
A cross-platform port of Hexen II game.
Odamex is a free, cross-platform, modern client-server Doom engine
Eureka is a DOOM map editor
Bots for the Half-Life mod Firearms 2.4 - 3.0
A free 3d game for PC that does not limit the player. Fight,Build,Gain
Fast small FPS using JOGL and JOAL
LGSL (Live Game for PHP 5.4-8+: online status for various gameservers
Volume 2 of ChaosEsque Anthology
PAK file editor for Quake engine games
Merges WAD files for Doom engine games.
DOOM / Heretic / Hexen source port with enhanced graphics and UI
3D-Accelerated open-source DOOM engine