I think there's one somewhere in Las Vegas, I've seen it in magazines. You suit up in an aerodynamic suit (that is to say, one that gives you some lift as if you were wearing a parachute), helmet and glasses and get into a chamber where there's a ginormous jet of air that gets fired up once the door gets shut. And you get to 'fly' with the knowledge that the worst that can happen is that they cut the air off too quickly. I've only ever seen it on things like Discovery Channel, so I don't know exactly where/how one can sign up, etc.

Sounds like the jet-pack trainer is the same idea.