Whats the most comfortable sleep you could imagine? To me I imagine that floating in space would be the most comfortable sleep you could get. Imagine being weightless and floating , no particular spots on your body to prop this way or that.
I believe the most comfortable sleep is on a hammock in the shade, by a waterfall. This has to be the most relaxing place, waterfalls are just that magical. I love hammocks, especially laying on them by the lake.