The name's cool. The idea's cool. And the execution? Well, it's pretty cool, too. Twelve South's new HoverBar ($80) is a unique new mounting solution for the iPad 2: a heavy-duty but flexible gooseneck pipe that attaches to the leg of an iMac, Cinema Display, or Thunderbolt Display, enabling you to keep an Apple tablet floating well above the surface of a desk -- off to the side of the computer's screen. The kit includes not only the hard plastic…