My buddy and i are on a pranking streak right now so ive been thinking of good harmless things i can do to him. His wife will give me access to his bike so im thinking i might fill his tires with water. Im thinking the easiest way to accomplish this is would be to use a cheap pump and unscrew it and fill the chamber with water. Any other ideas of what i could do? I put an add on craigslist for a free bag of potatoes and he got 10 calls within 5 minutes so im thinking i should lay low for a bit.