h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

This may be a little too silly, but...

How about song parodies, where someone takes a well-known melody and adds their own lyrics? Children do this a lot; for example:

(sung to the melody from 'The Batttle Hymn of the Republic')
'I wear my pink pajamas in the summer when it's hot,
and I wear my flannel jammies in the winter when it's not.
But sometimes in the springtime and sometimes in the fall,
I jump right in between the sheets with nothing on at all.
(chorus)
Glory, glory, how peculiar!
Glory, glory, how peculiar!
Glory, glory, what's it to ya,
if I jump right in between the sheets with nothing on at all?'

quizzical
(way too much time on my hands)

That's more a game than a topic, sadly