Cheap hot/cold fermentation chamber?

I live in AK and during the winter I am unable to brew a "non-explosive" ale due to low fermentation temps in the house. I've had enough and would like to build a fermentation chamber that will at least keep the beer at ale levels, and preferably one that would allow me to lager in the summer as well. I'm sure something like this has been posted already, but have been unable to find something that will fit my exact needs (space consumption and location being issues too).

Could I make a foam chamber like I've seen on this forum (which are designed primarily for keeping beer cold), but wire a light bulb in it? Also, is there a fire hazard to doing something like this?

Thanks!

http://www.williamsbrewing.com/CONTROLLER_HEATER_PACKAGE_P519C100.cfm

I need to keep a keg-orator from freezeing in an unheated garage and found this little gem. I haven't bought one yet so I can't vouch for it but it sounds like a safe way to do what you need to do.