Oh, great idea! I know exactly what you're talking about, too, everyone had those in college. I actually still use mine since it's really thick memory foam and therefore really comfy! Maybe next time I'm recording I'll strip it off my bed. Thanks for the advice!
Hey, I saw your post on your mic issues and you mentioned a recording booth.
If you're not worried about appearance and strapped on cash, you may want to drive by college dorms at the end of the spring semester. A lot of students buy these foam pads during the year that they use to cushion their beds, which perform essentially the same task as acoustic foam. At the end of the year, they usually end up in the trash because they have no use for them after the year ends or they graduate.