I thought this medieval joke funny, and it is philosophy-relevant, too:
Charles the Bald: Quid distat inter sottum et Scottum?
John Scotus Eriugena: Tabula tantum.
Which translates quite easily as:
- What is the difference between a sot and a Scot?
- Only the table.
You can read up on the provenance of this story, which goes back to the twelfth century, at PIMS. (Hat-tip: Cnytr, from Zadok)