Just stumbled across the OpenGL Samples Pack, which is a bunch of OpenGL sample code for advanced features... exactly the kind of thing I need to test if I've got PyOpenGL working... of course, they're written in C, but it's way easier to translate from C to Python than to come up with dozens of samples/tests by myself.  I don't expect I'll try wholesale translation, I'll more likely pick and choose those features that seem likely to need special wrapping support.