As one of its daily deals, Home Depot offers the 2nd-Generation Nest Learning Thermostat, model no. T200577, for $169.99 with free shipping. That's $34 under our mention from two weeks ago and the second-best price we've seen. (It's a current low by $26; we saw it for $10 less in December.) It "learns" how you set your home's temperature, downloads data, and can be controlled from your smartphone (via WiFi). Note that not all home HVACs are Nest-compatible; click here to see if it will work with yours. Deal ends today.