Today only, AltaTac via Rakuten offers the 3rd-generation Nest Learning Thermostat in Stainless Steel for $212.99. Coupon code "SAVE15" cuts it to $181.04. With free shipping, that's $3 under our mention from three days ago and the best deal we could find by $18. Improving on its predecessor with a slimmer profile and bigger display, this thermostat "learns" how you set your home's temperature, downloads data, and can be controlled from your smartphone via WiFi.