Chumsalmon, the one played on me is tough to beat for some 'odor revenge'. Just place some fresh sandshrimp under his truck or car seat after pinching off their legs so they can't crawl out from under the seat. They die off quickly but the horrid odor comes on in about 3 or 4 days; which really makes him wonder what and where it is coming from. Not much fun to clean up either, but shouldn't ruin any carpet because the shrimp kind of dries as it rots. Best to do in a guy's fishing truck, not his family car!