Pyglet and pymunk are python wrappers for fast libraries (for openGL and a c++ physics library, respectively) that are helpful in making games. I wrote a tutorial about combining the two to make 2D physics based games that are written in python but still perform well.

The 3 part tutorial covers using pyglet and pymunk and then integrates Numpy (fast c-like arrays) and pyOpenCV (another python wrapper for a fast c++ computer vision library). Check it out on the Pyrates are Cool python game dev wiki. [edit: link is broken. Here is the archived version]

Here are some of the videos I made of the results:

Basic physics:

Deformable terrain: