Is This The Coolest Bar Trick Ever? [Video]

Bar tricks are things I've always wanted to be good at. I'm not. Matter of fact, I don't even know any bar tricks. Watch this guy perform one of the coolest bar tricks I've seen in a long time. How do you think he's doing this?

Watch as the bartender makes the beer bottle cap seemingly hop out of the glass into another glass. The patron holds the cap, puts it in the glass, then magically it jumps into another glass.

How the heck is he doing this? At first I thought he had a string attached to the cap. After watching it a few times, I'm not sure this is the case. I don't really see him yanking on a string, or at least not hard enough to make the cap move as much as it does.

If you figure it out, let me know!