primate simple machines

Whether to prevent or encourage further philosophical discussion, here's what the internet says about simple machines: http://en.wikipedia.org/wiki/Simple_machines

What are the simple machines? There are anywhere between 4 and 6, depending on how picky you want to get.

- inclined plane
- wheel and axle (aha - it's not just a wheel, because what good is a wheel by itself?)
- lever
- pulley
- wedge (or maybe it's just an inclined plane?)
- screw (or maybe it's just a dizzy inclined plane? ... specifically, they mention the Archimedes screw, which is a type of pump... but I think the machine type would be a generic screw)

What simple machines have in common is the ability to convert small force / large distance to large force / small distance, or vice-versa.

Question of the day - what's your favorite simple machine? :)