Well.

The electrician just left. We're have a bathroom remodeled, including the replacement of two "heat lights" in the ceiling with a fluorescent or other fixture.

The heat light was a Joe Homeowner job. Recessed lighting with cedar fluff insulation packed around the box. Cedar is wood. Lights give off heat. Heat + wood fluff + air = ?

Go to the head of the class! Much of the wood fluff was actually charred.

Dodged another bullet!