By "simple" I actually mean "stoopid as a box of goose liver fondue".
See the photo below?
This is what is called a "helicopter". It's a little dealio that falls off some of the trees during the autumn here in Maine. The half to the right looks like an insect wing. The left half is a little cubby hole that is weighted by a "seed" enclosed in the cubby hole.
When you gently hold the "helicopter" by the weighted end and launch it upward, it floats to Earth rotating like the blade of a (you guessed it) a helicopter!
I really enjoy doing this.
Over and over again.
I am 58 years old.
I am stoopid as a box of goose liver fondue.