... Odd
Well, since there were no "other controls" listed, I went through every key and found you could change his color (1-9 keys). It's possible I missed something else, but it isn't very interesting. Yes, you can smack him into the walls. But the background seems random, as does the music. If there was more to it then just smacking him into walls, it would be better. And maybe make the background interactive?
Aside from its simplicity, it is well done, what is there. You can grab onto his head hands and legs with ease and send him flying around. But it's only entertaining for about 30 seconds or so.