If you look carefully at the picture, though, you'll see what looks like a lens flare* just below my left shoulder, mimicking the bands in my hair. I've seen this in several photos to date but I don't have any other examples. Despite that, my vague memory leads me to believe it has something to do with the Glow function of a prim (Web). The bands in my hair have a smidge of Glow added to them. When I get some time I'll have to investigate this, especially as of late I'm adding glow to more items that I build.
* "Lens flare is the light scattered in lens systems through generally unwanted image formation mechanisms, such as internal reflection and scattering from material inhomogeneities in the lens" (Wikipedia; Web).