Try making skateboard mod. Would look much like "SimpleCar.tbm" probably.
Mod where uke and tori have their own skateboards, and they are placed on the edge of a pipe... well that could rock.
Any skate parks would be cool too.
Not to mention that toris could ride this "skate park" not only on skate boards, but also - for example - on bikes, etc.
What do you think?