The third incarnation of Quake, which redefined (again) the way people looked at (and played) online games and which makes Unreal Tournament look like a high school physics simulation with stop-motion animation.
I used to run a games portal called accao.net a long, long while ago, and still rate running through q3dm6 with rockets exploding all around me as one of the most fun experiences I’ve ever had in gaming.

Back in 2001, I created a skin pack for the Visor model with two extra colors (green and yellow) and some level texture changes that we used for a Yorn co-branded tournament at the Internet World 2001 event in Lisbon.
I even did banner ads:


…and the year before, we gave away a scooter:

Resources:
| Date | Link | Notes |
|---|---|---|
| 2009 | ||
| Sometime ago | ioquake3 | arguably the best (cross-platform) enhanced runtime engine, with an amazing amount of improvements. |
| OpenArena | a derived open source effort. | |
| Older | ||
| Ages ago | cake | a map viewer. |
| Xbox port | ||
| QQQ | the Arena as performance art. | |
| Wolfenstein Enemy Territory (free) | Mac client available here | |
| Source Code | ||