Do not sleep is a great feature but I had turned it on and forgot about it and my machine stayed awake for days. There should be a time-out option that's easy to set -- for example -- it should say 1 hour, 2 hours, 4 hours, __ hours or until I turn it off. In my case, I turned it on while recording a podcast and knew that I wouldn't need it after an hour or so but of course forgot to disable it.
