Home - PocketMatrix.com
- Engine source port to Pocket PC
- http://quake.pocketmatrix.com/

Sketch Quake
- A Quake engine that features modern weapon view per player.
- http://sketchquake.blogspot.com/

ProQuake
- Improved and more debugged GL/WinQuake client, supports pings in scoreboard and cheat-free module and higher precision aim.
- http://proquake.planetquake.gamespy.com/

Fruitz of Dojo
- A port for Intel based Macs of Quake.
- http://www.fruitz-of-dojo.de/php/download.php4

Vengeance r2.1.3
- Features scriptable particle system, new lighting effects, motion blurs and more.
- http://entar.quakedev.com/

DarkPlaces
- Supports shell casings falling to the floor, improved bullet impacts, 32bit color alpha blended explosions and numerous other improvements.
- http://www.icculus.org/twilight/darkplaces/

Telejano - Home Page
- Modified Quake engine derived from TomazQuake with lighting caustic, rain effects, snow effects, dungeon lighting effects.
- http://telejano.berlios.de/wiki3/

QMB - GPL Quake Project
- Engine featuring advanced particle and rendering systems.
- http://www.flyingsaucepan.com/QMB/

Tenebrae
- Tenebrae is a modification of the quake source that adds stencil shadows and per pixel lights to quake.
- http://tenebrae.sourceforge.net/

Tremor
- High resolution supporting Quake client with built-in single player versus bots capabilities.
- http://tremor.quakedev.com

Qrack
- High resolution texture supporting client with many multiplayer features ported from ProQuake; based off of JoeQuake engine.
- http://www.quakeone.com/qrack

JoeQuake Project Page
- Supports high resolution textures, advanced demo and map menus, QMB particle support and numerous advanced graphics features.
- http://www.runecentral.com/joequake

Fitzquake
- A modified glquake with the primary focus on fixing the rendering bugs.
- http://www.celephais.net/fitzquake/