Heard of Polyphasic sleeping? The idea is that you compress your sleep into around 3 hours worth of power naps during a 24 hour cycle, thus freeing up 5 hours a day during which you will feel more productive, creative and energetic. This article concludes that this concept is total rubbish, however it does mention some other interesting sleeping patterns to experiment with if you are able to.

 http://www.supermemo.com/articles/polyphasic.htm