Seems like everything has possible firmware updates these days. Not just PC BIOS, but network cards, routers, printers, monitors, etc.
The other day I heard about a firmware update for a mouse. I wouldn't have guessed to look for that, and the manufacturer of the mouse doesn't have a way to get my attention. I wish Windows Update (or equivalent on other platforms) would do all this for me, but it sure doesn't.
Maybe you have a list of things you look for firmware on?