Cooling mattress recommendations

There are cooling mattresses? WHY WAS I NOT TOLD? It's probably something to do with me living in the arse end of nowhere. We hear about most things (apart from natural disasters) long after everyone else.

I'd be interested as long as they weren't covered in plastic. I'd rather lie on a concrete floor than sleep on a plastic/rubberised mattress. Let us know what you find out. Marg xxx