I'm glad you brought that up cam. I wasn't aware of all the Lego video games until now. Apparently they did make a game like steven talked about-
Lego Creator (video game) - Wikipedia, the free encyclopedia
It's PC and older but it sounds fun and truly creative.
[ame=http://en.wikipedia.org/wiki/List_of_Lego_video_games]List of Lego video games - Wikipedia, the free encyclopedia[/ame]
Btw I forgot about Bionicle being Lego. I bet if that came out when I was a kid I'd be in love with it.