What is the best possible bed, and method of sleeping in it?

Of course, a lot will depend on circumstance. So I guess it's specifically in relation to one of these situations:

Conforming
1) No budgetary limit, but is typical of the the way most people sleep (i.e. thick mattress (spring/foam, etc.), elevated off the ground, etc.)

Non-conforming
2) Atypical, such that you may face social stigmatisation, but also practical, feasible, and relatively affordable (e.g. hammock in bedroom?)
3) Atypical without budgetary concerns. Is emphatically the absolute best way to sleep (e.g. suspended in a sensory-deprivation tank?)

I am especially interested in /sci/'s thoughts on 2 and 3.