Working on the International Space Station means three things: it's crowded, you have to exercise to combat the effects of zero gravity, and your hair goes nuts. In this half-hour tour, Commander Sunita Williams shows us around the place during her final day onboard (back in November). It's utterly surreal -- it looks exactly what you'd expect a space station to look like, and Williams floats from section to section showing off the various areas, including the space toilet (just after the 9-minute mark). "That's, of course, for #2," says Williams. "This guy right here [grabs scary vacuum tube] is for #1...."

Particularly interesting to me is the constant background whir of machinery. It's no Star Trek ambient noise; it actually sounds like a loud window A/C unit. I wonder if that gets annoying after nearly a year in space. Check it out, folks:

Nerd trivia: the ISS is also known as Space Station Alpha, referring to its call sign.

If that's not enough for you, here's another tour: