You could eat a big meal of refried beans or stew made from old fish heads found in mtnbkr's closet before the flight, and give some gasseous payback to seatmate. The problem is that you don't know ahead of time if your seatmate will be supermodel or two seats worth of obnoxious flab stuffed into the seat next to you. If you always plan for the worst, the irritating seatmate would never go unpunished
