I got a bit of a scare, this morning. I had plugged my S2 in and put it to sleep (hit the power button), last night. When I picked it up, and hit the button, this morning, nothing happened! Hit it again, nothing. Held the button down for several seconds, still nothing. Thought I was in big trouble but tried another longer press. Suddenly, it booted. Hoping this was a one-off.