i.e. scattering your daily sleeping into several shorter blocks of sleep time, rather than just sleeping for a single big chunk of sleep.

http://en.wikipedia.org/wiki/Polyphasic_Sleep
http://science.nasa.gov/headlines/y2005/03jun_naps.htm
http://www.lifehack.org/articles/lifehack/information-list-of-polyphasic-sleep.html

and maybe
http://www.lifehack.org/articles/lifehack/effectiveness-of-power-nap.html
http://www.kuro5hin.org/story/2002/4/15/103358/720
http://www.stevepavlina.com/blog/2005/10/polyphasic-sleep/

Discuss!

I definitely want to give this a shot at some point, unfortunately I won't be able to try it within this year, due to school and living arrangements.
I'm damned curious abot the longtime effects of a successful adoption of that sleeping pattern, though. And I'm a bit too impatient to try this to wait a reasonable amount of time to see if Pavlina keels over as a side-effect (I say Steve Pavlina, because if someone's gonna manage to stick to that sleeping pattern for a looong while, it will be him).