I got a tip from Gadling.com that wearing sunglasses on the airplane will keep people from bugging you. Apparently, the key is averting eye contact. A neighbor will only begin to talk, shove, and elbow you if they've given you eye contact at any point. Don't ask me why that makes sense. So I tried it, and it worked! I kept my shades on my flight from IAH to LAX and no one bothered me at all. So to test the theory even further, I took my sunglasses off, turned, and locked about a second of eye contact with my neighbor. Lo and behold, not even 5 seconds after that, he asked me to get up to go use the lavatory. Coincidence? I think I'm just gonna keep my shades on.