I just heard a very good radio program on sleep called "While you were out". I've provided a link to the show's source: CBC's IDEAS series but sadly, there's not much to see as the CBC provides next to no information about the contents of their programs. Oh CBC - oh why can't you archive and document your radio programs online like NPR or the BBC?
From the program, I learned about the notion of "first sleep" and of segmented sleep in general. I would love to spend a couple months at a cottage with no electrical light and to experience what a "natural sleep" would feel like. That being said - at the moment I'd be happy with a full night's sleep (without being continually interupted by baby wanting to be fed).