Magnets have always been able to suspend soda cans in midair, haven't they? That's just basic science, right there.
The Magnetic Suspension Device—despite not having the most original name—can keep any bottle or can (up to 300g) dangling in its cylinder by placing a magnet on its top. And if I owned a bar that was trying just a little too hard, I'd be ordering them in bulk right now. [Chinavasion via 7Gadgets]