I slept on a ratty old imitation Japanese futon through years of college, and my neck and back still haven't forgotten the spongy cotton bed. I might try one again, but only if it's Panasonic's $2000 Programmable Pleasant Sleep Mattress. Hit the "Good Night" button and the 8 computer controlled airbags rise and fall sequentially over 10 minutes, stretching out your bod. There's even a foot warming function so you can lose the socks at night. Just make sure you don't activate the tentacle penetration mode, or you'll be sorry.
Panasonic's Programmable Pleasant Sleep Mattress [Tokyo Mango and The Raw Feed]