Well, before anyone freaks out and calls me crazy, you need to know that I work in a shop, around 450* extruders, and the rest of the shop is about 85* - 90* year round...
When we were using propane last year, I kept it at about 75*..... EXPENSIVE stuff right there. We had three months last winter that were $500 a month!!!
This year, we got the wood stove, and also a digital thermostat.
The thermostat normally reads anywhere from 80* - 90* all the time, and it costs me almost nothing
Even if I BUY all the wood to heat our house for the year, it will only be only about $500 :P
The thermostat is actually set to kick the furnace on at 75*, so that when we are gone, or if the fire goes out at night, the house will still stay warm. Since we fired up the wood stove, our propane furnace has only been needed to heat our house for a total of maye 12 hours, including being away from home for a day and a half.