WARNING:  This "light bulb heater" and the way in which it is constructed is NOT UL Approved. This design used with a high wattage light bulb will produce a fire hazard.  Before you attempt to construct this project, seek advice from a qualified electrician. 

We have an outdoor cat named Miss Minnie, who performs duties as our "shop cat".  Minnie is basically an outdoor cat who sleeps and eats in my shop - and prowls the property during the day.  Montana winters can be quite brutal, so I wanted to build her a home that would protect her from sub-zero temperatures because I don't heat the shop except when I am working.

Montana also has some king-sized predators like mountain lions, eagles and bears, so we lock Miss Minnie in the shop after dark to keep her safe.

The challenge was... how do we keep her warm without spending a fortune in fuel costs?  I decided to build her a basic cat house and install two low-heat sources.  One, was a heated pet pad that can be purchased at any pet store.  This would give her warmth from below.

The other heat source would be heat produced by an ordinary light bulb - from above.  Not wanting Miss Minnie to suffer through 24 hrs of blinding light, I decided to enclose the light bulb in a metal shield (read - coffee can).  The idea was to have the bottom of the can protrude through the ceiling of her house and have the top exposed.  The light escaping through the roof would provide illumination in the dark and keep the metal from getting too hot and risking a fire hazard.