This question was posed to the Usenet Oracle:

> If you drop a buttered piece of bread, it will fall on the
> floor butter-side down.  If a cat is dropped from a window
> or other high and towering place, it will land on it's feet.
>
> But what if you attach a buttered piece of bread, butter-side
> up to a cat's back and toss them both out the window?
> Will the cat land on it's feet?  Or will the butter splat on
> the ground?

And in response, thus spake the Oracle:

} Even if you are too lazy to do the experiment yourself you should be
} able to deduce the obvious result.  The laws of butterology demand
} that the butter must hit the ground, and the equally strict laws of
} feline aerodynamics demand that the cat can not smash it's furry back.
} If the combined construct were to land, nature would have no way to
} resolve this paradox.  Therefore it simply does not fall.
}
} That's right you clever mortal (well, as clever as a mortal can get),
} you have discovered the secret of antigravity!  A buttered cat will,
} when released, quickly move to a height where the forces of
} cat-twisting and butter repulsion are in equilibrium.  This equilibrium
} point can be modified by scraping off some of the butter, providing
} lift, or removing some of the cat's limbs, allowing descent.
}
} Most of the civilized species of the Universe already use this
} principle to drive their ships while within a planetary system.  The
} loud humming heard by most sighters of UFOs is, in fact, the purring of
} several hundred tabbies.
}
} The one obvious danger is, of course, if the cats manage to eat the
} bread off their backs they will instantly plummet.  Of course the cats
} will land on their feet, but this usually doesn't do them much good,
} since right after they make their graceful landing several tons of
} red-hot starship and pissed off aliens crash on top of them.