I see a lot of good ideas in this thread.

My vote would go to an idea that is simple and not time-consuming. People often failed to deliver the final game because they didn't have enough time. Our aim should be to get as many entrants as possible.
At the moment, I have many projects and I can only join if I aim low. If the theme allows me to get my game finished in two weekends, then I will definitely join.

Some ideas:
  • I like the idea of canned graphics. Just as random as possible. Prefferably with a lot of pictures of sheep.
  • A crazy shooter compo: Everyone should make a scrolling shooter and add weird enemies, obstacles and effects to it. The crazier the better. Could be combined with the canned graphics idea.
  • A scripted robot-war compo could be nice, but I think its still time-consuming to get the AI right.
  • A graphics contest: Who can make the prettiest particle effects with a delivered set of particle images.


Just some ideas.