Didn't propeller passenger planes of the 40s and 50s have sleeping berths for overseas flights? A journey on a prop plane might take 30-50% longer than on a next-generation jet.
I don't have anything against it, but I doubt it will catch on in these times due to the less revenue for airlines with precious space taken up with beds. Maybe just more spacious, comfortable seats would be a solution? That and hotels already disgust me--what kind of hygienic conditions can you expect when you're practically hot bunking with the previous passenger on your flight?