"I made a very important discovery at Camp Currie. Happiness consists in getting enough sleep. Just that, nothing more. All the wealthy, unhappy people you've ever met take sleeping pills; Mobile Infantrymen don't need them. Give a cap trooper a bunk and time to sack out in it, and he's as happy as a worm in an apple - asleep." -Juan Rico Starship Troopers (the book, not the movie)
This isn't to say that I couldn't go for another couple of hours of downtime, but after 9 blessed hours I feel soooooo much better!