Hmm. Probably "Sex Cow" by GWAR, on their best cd, "Carnival of Chaos". Here's a taste:
"Down in the dark where the wild things grow
We're in there where the people don't go
Licking and sticking and piercing the pud
Blowing and hoeing and covered in mud
We don't care what the people say
Every day is tree frog day
Still they say we live in scuz land
But that's where I met my cuzband
SEX COW! SEX COW! SEX COW!"
Beautiful! Well, I like it. Once you love Sex Cow, ain't nothin' gonna be the same.
I was going to name something off of Bruce McCulloch's "Shame Based Man," but the really funny tracks aren't actually songs, so...