OPCODE: Optimized Collision Detection
2002 - Pierre Terdiman
A free collision detection package that has been optimized to use less memory.
A free physics library. Open source under the BSD license.
Free physics library released under LGPL or BSD.
Physics SDK from nVidia, designed to leverage the power of GPUs.
Bullet Physics Library
Free open source collision detection and physics library. The emphasis is on the collision detection. zlib license.
Newton Game Dynamics
Free physics library. Closed source.
Open source and free 2D phyics library.