when I was sick and tired of my old, creaky, spring mattress, I wanted to buy a latex foam mattress, as I wanted to be as "green" as possible (what with so many mattresses littering the landfill taking about a million years biodegrade). Latex is natural rubber and will biodegrade much faster than conventional mattresses.

One thing to keep in mind when you get a "memory foam" type mattress is, if you tend to get hot in your sleep, you'll find yourself sweating a lot. The one I initially bought turned out to be a gross customer return mattress, and after wrangling through Better Business Bureau, they offered their equivalent, newer model which is latex foam plus wool and bamboo fibre topping which controls the heat and I must say it's MUCH better.

If you go the foam route, do your research and don't cheap out. If I'm sweating in the middle of winter, I can't imagine how intolerably hot it must be in the summer!!