"66% more people than normal chose the stairs over the escalator. Fun can obviously change behavior for the better." - Tom Stocky

This is awesome, but my afterthought is that the first time is fun, but everyday, it would no longer be novel, and people would go back to the escalator. If you tried to make every set of stairs fun, you'd get a sort of 'fun fatigue' effect as well. It works well in small doses, but there's an even cheaper and easier way to fix it if you really want to: remove the esclator, use elevators for disabled. :) - Ray Cromwell