Benchmarking with the four demo (v1.32) without sound:

quake3.exe +set s_initsound 0 +timedemo 1 +demo four

nV News - Guide To Benchmarking - Page 2 from June 2000.

To loop demo1 until manually interrupted:

set demoloop "demo demo1; set nextdemo vstr demoloop"
vstr demoloop

r_mode -1
r_customwidth 1440
r_customheight 900

Source:Running Quake 3 in Widescreen

To set it like it was on Quake 2:

cg_oldRail 0
color1 7
color2 3

Source:GameWinners.com - Quake 3: Team Arena (PC)

When starting the installation program, the following error message is displayed:

Verifying archive integrity...tail: cannot open `+266' for reading: No such file or directory
Error in checksums: 433440451 is different from 2693581780

Open linuxq3apoint-1.32b.x86.run in a hex editor, for example KHexEditor, and change all

tail +266

in

tail -n +266

Save the file (with another name).
Then execute the modified installation program with:

linux32 linuxq3apoint-1.32b.x86.run

When starting Quake 3 you don't have audio and the following error message is displayed on the console:

/dev/dsp: Input/output error
Could not mmap /dev/dsp

To get sound working with quake3-smp.x86 and quake3.x86 the following two commands have to be executed to get the OSS emulation working:

echo "quake3.x86 0 0 direct" >/proc/asound/card0/pcm0p/oss
echo "quake3-smp.x86 0 0 direct" >/proc/asound/card0/pcm0p/oss

See also:NOTES ON KERNEL OSS-EMULATION

Open the console and execute:

set loop "demo four.dm_68 ; set nextdemo vstr loop"
vstr loop

Source: Tom's Hardware - Forum - Overclocking - How to get Quake3 Loop ??

Quake 3 downloads at QuakeUnity.com

FileFront - Q3 Simpsons Map

UI Enhanced
Navy SEALs: Covert Operations
Reaction Quake 3, Reaction
Catch the Chicken
The CorkScrew mod
OSP TourneyQ3A
ChallengeProMode
Rocket Arena
Unreal Arena
True Combat
True Combat moddb pagina.
Q3Rally
Bid for Power
Painkeep Arena
Xtreme Arena
Afterwards
Generations Arena
Loki's Revenge CTF
NoGhost Server Side Mod

Quake 3 mods op moddb.com

Smokin' Guns

Urban Terror

GitHub - Barbatos/ioq3-for-UrbanTerror-4 The officially supported ioquake3 engine by the Frozen Sand Development Team for the game Urban Terror 4.x
GitHub - undeadzy/urbanterror_4.1.1_ioquake3 Undeadzy's version of the client/server for Urban Terror 4.1.1. Unlike 4.1.1, this merges in the latest ioquake3 changes.

Code3Arena
Tutorial Backups
Quake3World Mod Programming
Q3Devel - Links

Running a Quake III Arena server on OpenBSD

CleanQ3
evolutionQ3 (dead link) FreshPorts - evq3 lists it as “Marriage of XreaL and Icculus.org Q3 w/ Improvements”.
Spearmint s a heavily modified version of ioquake3. Many modding improvements make it not compatible with Quake 3 mods (QVMs/DLLs) or replay demos.
GitHub - PJayB/Quake-III-Arena-D3D11 Quake III Arena GPL Source Release for x64, Direct3D 11 and, optionally, for Windows 8.
GitHub - kennyalive/Quake-III-Arena-Kenny-Edition Quake III Arena with Vulkan support. See also:Medium - Quake 3 Vulkanized, CppDepend - Comparing the codebase of the original Quake3 and the kenny edition one..
GitHub - ec-/Quake3e is a modern Quake III Arena engine aimed to be fast, secure and compatible with all existing Q3A mods. It is based on last non-SDL source dump of ioquake3 with latest upstream fixes applied.

Fabien Sanglard's Website - Quake 3 Source Code Review

ioquake3
Subversion (SVN) repository (last revision before move to GitHub is rev2398): icculus.org - ViewVC - quake3
Git repository (home of the current version): GitHub - ioquake3/ioq3
GitHub - undeadzy/ioquake3_mirror Unofficial ioquake3 mirror from SVN for forking.
GitHub - ioquake/three A GPL (v2) and Creative Commons (for the assets) game for the ioquake3 engine.
GitHub - ioquake/launch The launcher for ioquake3.
GitHub - icecrime/docker-ioquake3 Dockerfile for running ioquake3 in a Docker container.
GitHub - AlienHoboken/node_ioquake3_client A node.js headless client for the ioquake3 engine

Q3Devel an IDE made for Q3Coding. Source code available under the GNU GPL.