Got this in an email, but thought it was pretty good:
If you are sitting next to someone who irritates you on a plane or train...
1. Quietly and calmly open up your laptop case.
2. Remove your laptop.
3. Turn it on.
4. Make sure the guy who won't leave you alone can see the screen.
5. Close your eyes and tilt your head up to the sky.
7. Then hit this link:
http://www.thecleverest.com/countdown.swf