The rolling-release Arch Linux distribution has just enabled floating point textures for Mesa. This was the hotly-debated feature for Mesa that provides OpenGL floating point textures and render targets, but is disabled by default since its protected by patents in the United States and elsewhere. Arch Linux users when building new versions of Mesa will receive this support irrespective of their physical location...
June 1, 2011
Arch Linux Enables Mesa Floating Point Textures
Read more at Phoronix