Here is a link to a gardening idea that would work beautifully as a heat source for any Proofing Box.
Just copy the following link and paste in address window if the link does not work.
http://www.vegetablegardener.com/item/11658/diy-heat-mat-speeds-seed-starting/?utm_source=email&utm_medium=eletter&utm_content=20111221-heat-mat&utm_campaign=vegetable-gardener-eletter
How would that be better than one regular incandescent lightbulb?
How would that be better than
How would that be better than one regular incandescent lightbulb?