To the other bonehead writers out there, you ever come up with a story while you're falling asleep?

And then I'll wake up and the story has progressed and I have no idea how it got there, or I'll be like yep, I'll write that down in the morning but nope no good I forget it all. I was thinking of something last night about a chick taken by raiders in the 100 years war, I was actually coming up with the words and after they've done the nasty a bunch of times they run her through with a sword and leave her disemboweled on a hill, and she keeps trying to put her innards back in but no good, they keep spilling out. I remember that bit!!! The ending.