Rules:
Goal wheel must be connected or touching your bot at all times (ex: carrying it in a basket is ok)
limit of 7 power wheels
limit of 2 neutral wheels (un-powered) not counting goal wheel
Limit of 16 water rods
Limit of 8 wood rods
Contraption must be built on one side of the arena (marked by single water rod)
I'll think of some as I go.
You could suggest some rules too if you'd like.
Here's the first bot:
http://FantasticContraption.com/?designId=3829319