you will need;

(1) Cat (preferably freindly)
(1) Slice of toast buttered on one side
(1) Bottle of strong glue OR (1) Roll of sticky tape
A second floor window.

Method;

1) Use your tape or glue to attach the slice of toast to the cat with the buttered side facing out.

2) Drop the cat out of your second floor window.

Result; due to the miguided physics of common knowledge, the cat will reach the point where it is about to touch the ground, then stop and rotate indefinitely. This is because the universe cannot decide weather the cat will land on its feet or the toast will land butter side down, as either way in in direct contridiction to the absolute truth of the other.