So back in my Uni days, I worked on a game called "War Worlds". It was supposed to be a real-time strategy game which features a "repeating" map - so if you scroll to the end, it just wraps back to the start again. The other "interesting" feature I had thought of was that you'd have separate bodies and turrets, but that idea was already done in Warzone 2100.
I still kind of think the "repeating" map was an interesting idea, so I've decided to resurrect my project, just to see where I can take it. Here's a screenshot of what I've got up to so far:
This is the editor, which will be for editing the heightmap, adding trees and initial buildings and so on. Most people use import images for those kinds of things, but I think this way will help to encourage others to contribute (heh).
Anyway, it's still in the very early stages and I don't even know if I'll finish it, but it's been interesting so far. It's also given me the opportunity to get back into C++ and (as you can see in the screen shot) I'm learning wxWidgets as well.