Originally Posted by Tom Stormcrowe

There's always the Felis Domesticus/Buttered Toast antigravity powered electrical generator....

Attach a piece of buttered toast to the back of a cat, butter side up. Drop the ca//toast combination, and since toast always falls buttered Side down and a cat always lands on their feet, the combined effect is to suspend the cat in midair, rotating. Harness the rotational energy and you can generate 410-15KW with a relatively light weight unit

The Cat/Buttered Toast Paradox