The Nouveau open-source driver for NVIDIA GeForce 8/9/200 graphics cards is now faster than NVIDIA's own driver, according to a report by Phoronix.
You can view the benchmarks over here.
"With a little work, the group of community Linux developers
without any corporate backing have clean-room reverse-engineered the
proprietary NVIDIA GeForce graphics driver to write a fully open-source
2D/3D driver for NVIDIA graphics cards. After years of work, this
open-source driver called Nouveau is now just as fast -- or faster --
than the official NVIDIA driver when running it on low-end GeForce
8/9/200 series graphics cards."