Silencio.

Today, as part of my job, I got to hang out in an Anechoic chamber. If you've never been in one of those, it's basically a room so sound-proof that it's completely silent. Even small sounds (like breathing) are swallowed up by the huge baffles on the walls, floors, and ceilings. One of my co-workers didn't go into the room, stating that it wierded him out.

I can see why. Not that it weirded me out at all, but it was an interesting experience. Complete silence has interesting effects on your head. You become very aware of your ears, to the point where you feel like your eardrums are swelling. Your equilibrium seems messed up. You get disoriented very quickly, and realize that, without reference sound, your brain is doing backflips trying to figure out what's going on.

Far from being freaked out by the experience, I'd be interested in hanging out there more often, for hours at a time. If you ever get the chance to go into an Anechoic chamber (and I don't know how you would -- it's not like they're advertised in the yellow pages), I highly recommend it.