Sleep Blogging

I have not yet found any other blogs focused on either biological rhythms or sleep, but I found two blogs that look at sleep from a more personal perspective:

Sleep is for lazy people
http://nomadichermit.blogspot.com/2005/01/sleep-is-for-lazy-people.html
http://nomadichermit.blogspot.com/2005/01/sleep-is-for-lazy-people-ii.html

Sauna-Ukko
http://suana-ukko.blogspot.com/