Yes, the water tank connects to the pad, and pumps water through it to keep everything at a specific temperature! The pad goes under your fitted sheet, and has a soft upper layer. And you can use the remote to adjust the temp without having to get up! It comes in half or full sizes, too, so you and your partner can have separate temperatures. Curious? Then take advantage of the a 90-day sleep trial with free shipping and returns! It also has a two-year warranty.
Promising reviews: "ChiliPAD has changed my life!!!I used to wake up multiple times during the night, soaked in sweat. No more! I get up in the morning feeling so much more rested — I didn't realize what a poor night’s sleep I was getting." —Janice K.
"This is the only cooling pad needed to get through sleepless nights related to hot flashes or heat sensitivity. I tried more than one less expensive 'cooling pad'. Nothing helped me sleep cool for more than an hour until my husband bought me the Chilipad. It works as advertised and it is worth the price." —Angie V.
Get it from Chili Technology for $499+ (available in sizes half queen–half Cal king or regular queen–Cal king).
(FYI, they make an even fancier version with noise control, an auto-clean function, better pre-heating and pre-cooling, app control, and a slightly nicer pad for $699+; if you scroll down that page you'll see a link to the Consumer Reports writeup on both products (PDF) if you're trying to decide which model's right for you.)