Brightness Display randomly appears on screen???

[MikalE]

What would cause the brightness display to randomly pop up on the bottom of the screen when it has not been adjusted?

It did this about a year ago and I had to reboot the machine. It didn't do it again until this morning. I killed the display process to try and avoid a re-boot until it was convenient to do so, but the machine kept logging me off so I ended up re-booting anyway.

Why would it do that?