No doubt we've seen some snazzy takes on mousing instruments, but when Popular Science dubs your twist on the critter we couldn't do without an Invention of the Year, you've accomplished something. A team of WPI undergraduate students were able to win such an honor by crafting the MagicMouse, a "three-dimensional computer mouse" that allows users to "control and manipulate items on a computer screen just by pointing at the monitor." While we've seen similar ideas for helping disabled individuals interface with a computer, this wee iteration actually fits around one's finger and "uses an array of receivers to track the motion of a tiny ultrasonic transmitter." The cursor is moved by waving one's hand back and forth, while moving closer and backing away enables zooming functions to be utilized, which should make handling those CAD drawings a good bit easier. Perhaps most notable, however, is the relatively low cost of assembly, as the entire contraption (rechargeable Li-ion and all) cost just $155, and we're sure you know how far that could fall if a bulk buying manufacturer brought it to commercialization. A few more pictures after the jump.