Dick's favourites when they've had a few wines, especially when a few old retired headmasters (Principals in Australia) get together.

Here's one he likes

"There was a young man of Eau Claire,
Enjoying his girl on the stair;
On the forty-fourth stroke,
The banister broke
And he finished her off in mid-air..."

Quite 'politically incorrect' of course...
He also loves one about "Roger the Lodger"