Vaguely related question:

I've always had polyester fiber-filled pillows. After a few years, they get lumpy, but they don't cause me any allergy issues and they provide enough support, no matter whether I'm on my side, back, or front.

I recently stayed at a friend's place, and he had a Tempurpedic foam pillow of some sort (latex?) that was surprisingly comfortable. It had one side thicker than the other, presumably to give you more options for how you want to use it. Poking around, I see a wide diversity of different pillow types out there (memory foam vs. latex, never mind odder things like pillows filled with buckwheat hulls -- basically finer-quality beanbags). Has anybody here investigated the diversity of pillow types? We're ready to get some new pillows.