SHINE hair gel.I don't know if this would work with just any hair gel, but it sounds interesting.
I discovered, when I had hair, that the gel caused my scalp to look shiny. People kept commenting on the thinning hair and the shine of my scalp. So, when I took all my hair off, I thought I'd go back and see if it would work as a shiner. Use a pea sized amount. Instant shine. It must be a plastic. Works great and lasts all day.
Not everyone wants a shiny head, of course, but if you're looking for a little extra brightness up top, it might be worth a try.