Toss and Turn Logger - Did you get enough sleep last night?

An important but difficult question to answer is "How well did I sleep last night?" It would be nice to have some objective measure of that other than "clock time" because sleep quality varies.

I've been experimenting with an Ipod Touch App that uses the accelerometer to log my "tossing and turning". The idea is that deep (and restorative) sleep correlates with absence of movement. It produces a nice graph and stats, and if you buy the 99 cent version, you can keep a long term sleep log in an Excel spreadsheet. Over time one can perhaps correlate individual daytime performance with nighttime sleep quality to establish "personal limits"?

The APP is marketed as a fancy alarm clock that optimizes your wake up time, but logging my sleep quality seems to have more value for me.

http://www.azumio.com/apps/sleep-time/ Free to try.