It's hard to think of a more iconic comedy routine than Abbott & Costello's "Who's on First." Indeed, in 1999, Time magazine named it "The Best Comedy Sketch of the 20th Century." Take that, Cheech & Chong! "Who's on first?" has become a catch-phrase for any confusing situation, and linguists have used the exchange as an example of all sorts of concepts, like "dialogue act disambiguation" and "use-mention indicators." It's so deeply ingrained in our cultural consciousness that it's easy to take for granted, or perhaps not even bother actually listening to. But download this classic — it's still really funny, a marvel of timing, teamwork and wordplay.

The origins of the piece are actually really controversial, with several credible versions of the story, but suffice it to say, similar bits had been kicking around the burlesque circuit for ages, and Abbott & Costello debuted theirs on Kate Smith's popular radio show in 1938, picking up on baseball's longstanding tradition of nicknames, like "Pepper," "Preacher" and "Flash," and coming up with maddening monikers like "Who," "What" and "I Don't Know." The show's producers allegedly didn't think the bit would translate to an audio-only medium, but it was an instant hit; for… read more »