text: what is it when you're sleeping ? you wake up because you feel there's a tremendous weight on you that keeps you from moving and speaking? it's very creepy and you can feel and hear but you can't open your eyes, can't even let out a wimper or moan....scary.it doesn't last too long but when it's over you're heart is going at a rapid pace and you can finally move and breath normal. it is medical condition called "sleep paralysis" . if you want more info, please click on the clink below;  http://en.wikipedia.org/wiki/sleep_paralysis  sorry guys, don't want to disappoint you but there is no "satan" involved. :))