While I've had the typical "I'd like to write a novel some day" thought, I don't think I'd be able to motivate myself to stick to a single topic for an entire month. But perhaps I could tweak the idea to do something similar. I was thinking of writing articles on in depth topics about video games and the fictional cultures within them. Everything from economies, to diets, etc. Just random various things in games that people don't normally think about. I already enjoy discussing this type of stuff, so I think writing articles on it would be neat.
Novels don't have to be restricted by a single topic! When I write I find a fun little "game" to play with myself is to try and connect as many different ideas as I can in a some what decent manner. Besides, writing is like anything else in like. It's take practice!