Cat Piss.

A 12 gauge is more effective!!
Fix the cat, shoot the idiot owner.
Rock salt and cracked pepper corns. One guy I know mentioned popcorn. The thought is the heat from the powder burn will pop it, but I doubt it would work.
I also think some pig manure in a ballon fired out of a potatoe launcher might work when applied to the back of the head. Want to act like a **** head, may as well look and smell like one. But that would likely result in me or you being charged. But I do like the idea, a lot out there these days seem to qualify for being recipient.