I've slept in a sensory deprivation tank several times. It's pretty trippy...you spend a lot more time in REM state and your dreams dance the line between dreams and hallucinations as a result.

I like that they were playing Patsy Cline on the tape deck.

I just realized that I had Patsy Cline playing in my head since I read that line.

I'd always wondered what it would be like to sleep in a gravity a fraction of that of Earth's - whether or not it would be more or less comfortable. Sounds like it actually would be more comfortable, had the astronauts had accomodations more equivalent to those on Earth.

You can try it. Put on a wetsuit and a mask and sleep underwater.

Or use a Sensory deprivation tank, you can get access to them commercially. You can even use a heater and a bathtub to makeshift one.

Not quite; while the net downward force on your body is indeed less underwater, the pressure on all sides is greater. In particular, if you are at rest, the force pressing on your underside is equal to your weight plus the weight of the column of water pressing down upon you. (This force is indeed what keeps you afloat!)

The experience reported by these astronauts is that of the pressure underneath them being less. I can think of no way to simulate this on earth, save napping in near-freefall (e.g. while parachuting, or while on the Vomit Comet). This does not strike me as a sound idea.

I knew a rockstar big iron developer at British Telecom who had a home made tank he used to mediate in.

Apparently he once saved one of the big quarterly billing runs from disaster.