[FlamesAllTheWay]

EDIT: Hmmm, the myth is a little different than what I thought, rendering my prediction useless.

Originally I thought the treadmill was going forward and the plane was sitting stationary on the treadmill moving forward as fast as the treadmill would take it. I would guess the plane would take off just fine as long as the treadmill was fast enough. Sorta like on an aircraft carrier.

For what the myth actually is (plane moves forward as treadmill moves backwards), I'm not so sure. The plane itself would still be stationary regardless of how fast the treadmill was moving backwards. I'm no scientist but I say this one gets busted... would be cool if it actually worked though.