Just a normal harp ... except instead of strings, it has fucking lasers. If you could kill Bond with your Nanoguitar pick, you'd use the Laser Harp you'd to wipe out the rest of MI6 in one hellish afternoon of fire, blood, and inappropriately mellow tunes.
It's a simple mechanism: Whenever a laser is broken, a corresponding note is produced. And while the notes you can play are limited by the number of lasers, there are an infinite number of ways to break those lasers - digital manipulation, dance, object interaction, or just the controversial but always crowd pleasing 'dong-pluck'.
There are three different types of laser harp: Framed, image recognition, and infinite. Framed harps look exactly like a regular harp, if you ignore the lasers (they are rather noticeable, however, in that they are lasers). Image recognition harps forgo the visual lasers in favor of invisible ones, and are largely purchased by people who never learned what fun was. Infinite Lasers are, well...we'll let this description from laser harp enthusiast Steve Holby describe them: "a fan of [laser] beams shoots up from the floor into the night sky."
Laser Fan: The only objectively bitchin' kind of fan.
Holby used to sell plans online so you could build your own, but they were taken down. Now your only options are to get him to build a custom model just for you, or else design and construct your own. But you're spending at least part of your day reading Cracked; the odds say you're not the most 'productive' human being around.
The Zeusaphone's name is a play on "Zeus" and "Sousaphone" -- the former being a mortal-bonin' Greek god, the latter being a large, round ball that quivers in response to fun (we don't actually know what a sousaphone is. It was from Cat in the Hat, right?) The Zeusaphone is basically just an ordinary Tesla coil that has been harnessed to play music. Here's the Mario theme song on one:
That's right: We have not only officially tamed, but completely humiliated lightning.
You can get your own from Zeusaphone.com because they rent out lightning guitars on the internet now. If you've ever needed a cue to believe you're living in the future, that last sentence was it. Your choices for rental are the Z-26, which produces 26 inch electrical arcs, mainly used for smaller venues; the Z-45, which produces 45 inch arcs, mainly used in expos and larger shows; or the Z-80, which produces 84 inch arcs, mainly used to threaten congress if they don't give in to your demands promptly enough.
Wikipedia tells us that the Zeusaphone works by discharging sparks that are "digitally modulated so as to produce musical tones. The high-frequency signal acts in effect as a carrier wave; its frequency is significantly above human-audible sound frequencies, so that digital modulation is able to reproduce a recognizable pitch. The musical tone results directly from the passage of the spark through the air. The flexibility of the sound is limited by the fact that the solid-state coil produces square rather than sinusoidal waves; but simple chords are possible" So in other words: Magic.
It's magic made by wizards.
For more examples of art and science colliding in a badass explosion, check out 5 Works of Legitimate Made Science Passed Off as Art.