I have soooo many ideas.
How about a little cart level in which they could get items off the track and throw them at the other carts? I would call this one LBP Cart.
I would also create these spheres with a high gravity value and they would run around them and jump from one to the other. I would call this one LBP Galaxy.
And the I could also make a level in which they play tennis. I would call it LBP Tennis.
If I could make a board game, I would call it LBP Party.
The possibilities are endless :)