Nvidia has open source drivers at nvidia.com
I just visited driver page at nvidia.com and there is open source driver for nForce chipsets instead of binary one. This is step in right direction. However there is some little things which do not look well in my opinion. These open source drivers are just those available in kernel sources. I'm little disappointed. I hoped Nvidia programmers will put some power in these source files extending drivers features.
This hurts nForce1,2 users only. Open driver supports only codec. The APU and Soundstorm support is dropped. No hardware acceleration, no OpenAL library. What a pity, this was the only one proprietary fully hardware accelerated OpenAL in Linux.
First look at source code shows that only some nForce3,4 users can use hardware acceleration. Why other chips are not fully supported?
As I said before I think this is step in right direction. I hope Nvidia will improve these open drivers by adding features known from older binaries.