I just found another example from that same Mudcat thread:

Subject: RE: Naughty kids'greatest hits
From: Laoise - PM
Date: 15 Sep 97 - 10:24 AM

We had a different version to Miss Lucy...

Mary had a little lamb, she thought it rather silly,
She threw it up into the air and caught it by it's...
Willie was a sheep dog sitting on the ground
Along came a bee and stung him on his....
Ask no questions tell no lies,
Ever see a p'liceman doing up his....
Flies are a nuisance, bugs are worse
And this is the end of my silly little verse.

-snip-

[I'm re-posting these examples with all due respect to the original posters]