The Nest is a great thermostat, especially with the Nest plugin for Vera.
I just wanted to share one thing that I do with the Nest plugin and PLEG that I think is cool.
I have central heat, but not central air conditioning.
I use PLEG to automatically turn the fan on, without the furnace on, when the temperature in the house is above a certain level or humidity is high. This helps circulate cooler air through the house.