Nest

Recently got the Ecobee 3 lite, and so far have been very happy.

Picked that over the Nest as it seems that it gives a little more control over various thresholds etc. My system is a little more complicated than the OP's as I have a heat pump with a gas furnace as auxiliary heat and the Ecobee lets me set how long the heat pump will run for before calling for the furnace as well as a load of other settings.

For a single heat source a standard thermostat should be fine though.

Yep, all we have is a furnace as well. I tried connecting it, and it would work for 5 minutes, then turn off.

I've been running a two-wire furnace-only setup with a Nest 2nd gen thermostat for a couple of years now without a problem. FWIW, the wiring harness configuration is: black to 'W1' and red to 'Rc'.

Honeywell makes lots of wifi thermostats.

I've been running a two-wire furnace-only setup with a Nest 2nd gen thermostat for a couple of years now without a problem. FWIW, the wiring harness configuration is: black to 'W1' and red to 'Rc'.

I've been running two wire for a couple years as well with no issues. great little gadget.

I've been running a two-wire furnace-only setup with a Nest 2nd gen thermostat for a couple of years now without a problem. FWIW, the wiring harness configuration is: black to 'W1' and red to 'Rc'.

Mine is a 2nd gen as well. After days of back and forth it simply wouldn't work and I ended up pulling new wire.

Sweet that you guys didn't have to go that far.