Since there are threads on sex songs (sort of) and parodies, it seems like a good time to take up Peter's suggestion.

Son of Broken Token
(Tune: John Riley, etc.)

As I roved out one fine May morning,
A lark did sing--I thought it wept--
And there I met a fair pretty maiden.
She looked as though she hadn't slept.

I'm always ready in the morning,
I've been that way most of my life.
She drove me wild, and what I told her
I now forget, but it ends with "wife".

She said, "Oh no, I loved a sailor
Who I met last night, but he fled arrest.
He took my ring, made a broken token."
She drew it out from between her vests.

I felt around within my pocket,
Found the half a ring I keep in it.
We matched them up--it was not perfect.
Said I, "So what? We'll make them fit."

That morn I proved my honour long, boys.
We worked with main, we worked with might,
With elbow grease and lots of patience.
Within an hour it fit just right.

Come all fair maids, heed well my warning:
When the token fits, take action soon.
Love that feels strong on a sunny morning,
It may turn weak ere the clock strikes noon.

Copyright 1998 by Jerry Friedman. I hereby place these lyrics in the public domain. If anyone is so tasteless as to sing them, I'd appreciate credit.