I'm partial toward "Billy's Mule," by the New Christy's Minstrels, a song so dumb that it singlehandedly ended the 1960s folk music boom, IMHO. It's so stupid that I've recored it for my next CD. Until then, you can hear the New Christy's Minstrels version:



http://members.cox.net/pvsharp/tlg/tncc.html