ioquake3
The ioquake3 community effort to continue supporting/developing id's
...It adds numerous quality-of-life improvements such as VoIP support, AVI demo capture, improved console completion and history, and optional Ogg Vorbis support. ioquake3 also improves portability and maintainability by supporting x86_64 on Linux, MinGW builds on Windows, and various other operating systems, and even provides web support via Emscripten.