It would be awsome to have a good game that can aid sleep. Not sure quite sure how, but nice relaxing music and good colors would be a good start. Nice slow gameplay could be a Plus.
Well, I guess you could have a game with incredibly slow game play. All games have a minimum concentration requirement, unless you're talking about a game before you go to sleep. Everything you can do in a game like that, you can do yourself. Play soft music, look at soothing images.
Computer screens keep you awake at night. It's the type of light the screen makes that wakes your brain up. So no, I don't think that idea is possible.
And who'd want to sleep while there computer's on?
well you could try those escape games. or the "colour my" series. there are also those kind of games with the bad (but suiting) graphics like "where we remain" "[together]" "i fell in love with the majesty of colours" and.... sorry forgot the last ones name but it was about a dragon starting from the egg phase and ending in the hero phase.
