Editor's note: If you don't count the human voice as an instrument (and honestly, it depends on the human -- like, would you call Marge Simpson's voice "an instrument"? Case closed.), the guitar is the most widely played instrument in the world. And in addition to all the things that make it appealing, it's inherently beautiful. Curvy, made of wood, fits nicely within the embrace of its owner; what could possibly go wrong? The answer: if we're talking about a guitar wallpaper, nothing. Real life, that's another matter. Meanwhile, this is one of the prettiest collections we have, so check it out and rock on!