Tuesday night's [article id="1635570"]slightly surreal episode of "American Idol"[/article] featured a handful of eyebrow-raising moments. As the top nine contestants dipped into the Lennon/McCartney song catalog, we saw Lee Dewyze bring out a bagpiper during "Hey Jude," Tim Urban turn "All My Loving" into a rockabilly shuffle and Michael Lynche spin "Eleanor Rigby" into a revivalist meeting. But the evening's most head-scratching moment once again came courtesy of Crystal Bowersox, whose surprisingly middling version of "Come Together" was rescued by the bizarre addition of a didgeridoo in the arrangement.

The didgeridoo (sometimes spelled "didjeridu" or referred to as simply "didge" or "didj") is a traditional Australian pipe instrument that is little more than a hollowed-out cylinder of wood. When played, it emits a low droning tone that is meant to evoke the mysteries of nature (according to Aboriginal Australian tradition). The simple tones are used to accompany ceremonial dancing and singing, though the instrument can also be played for recreational purposes. Skilled didgeridoo playing requires mastery of circular breathing in order to make a continuous sound. Anthropologists are unsure just how old the didgeridoo is, but archeological evidence says that it could have been around as long as 1,500 years ago.

Though primarily used in Australia, the didgeridoo has found its way into traditional Celtic music, trippier versions of electronic dance (Aphex Twin's Didgeridoo EP explores the relationship between trance and the didgeridoo) and certain forms of jazz. It even makes occasional appearances in pop music, most notably in Australian superstar Xavier Rudd's crossover tracks, which earned him touring spots with the likes of Jack Johnson and G. Love and Special Sauce.

What did you think of Crystal Bowersox's use of the didgeridoo? Did it add to her performance or was it distracting? Let us know in the comments!

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