I use PyWeek to explore technologies I wouldn't otherwise get to play with. Sometimes something interesting pops out, sometimes not.
I'm still learning the secrets of good game programming. I first picked up OpenGL via Hill and Kelley's "Computer Graphics using OpenGL", and pyglet.
My first PyWeek was a great success (although I never submitted an entry)! My library GEFFA benefitted from comments, and I hope it's now in a fit state for other people to consider using it this time round.