I still haven't figured out what some of these blank extra keys do, or could do, looking for a way to map them to functions once I know they're being registered as input.
There are two extra keys around the space bar keys, three buttons above the number pad, and three labeled keys after the F12 key. The labeled keys look like hotkeys to power on/off, wakeup, and hibernate a computer. I've not yet tried these. The other five seem to do nothing.