A Memory Foam mattress pad is a wonderful thing.
If you toss the comforter over it when you get out of bed in the middle of the night, it retains it's warmth while you visit the bathroom, feed the cats and clean up the mess that one of the cats made throwing up all over your antique Lane chest. After going through all that, you can crawl back into a nice warm bed.
On a cold evening, the surface of the pad feels like corrugated cardboard. The instant you lie down on it, it softens and molds to your body in a way no other mattress can.
Best $109 I ever spent!