Originally Posted by ChuckO
I'd be cautious using a halogen bulb, haven't seen one that runs cool enough not to present a fire hazard. I use an old 60watt boot drier and have found that to be sufficient to hold a 9cf freezer to 65 deg in my unheated garage in January. You really don't need much heat, although it stays on longer than a higher power heat source would.
It's actually an outdoor lamp w/ a protective glass cover, impervious to the elements. I will check out some of the other options though, not crazy about the light even though I ferment in buckets. Holds temps steady though.