Froli is a (plastic, poly, synthetic...?) spring system that is adjustable. We just assembled it on the boat today and layed a sheet of cardboard over it and layed ourselves down. Amazing! What we bought was an amount sufficient for a queen bed, about $400. Although our bed is more of a trapazoid. Well, a queen trapaziod. We're not connected in any way with the seller except as having purchased our own. http://nickleatlantic.com/. We are planning on three layers of 2" blended Talalay, divided down the middle, for a total of six "elements" in the bed. This is necessary because of needing to access steering equipment below the bed.
So if you're a student on the move (or a boater) consider this: a Froli on the floor and one or two "somethings" on top.
So if you're a student on the move (or a boater) consider this: a Froli on the floor and one or two "somethings" on top.