I've been wanting to play with RADIUS, but motivation today quickly led to
the discovery that is not going to happen short of dragging an old P2 out of
the basement, finding a NIC somewhere, and hoping for the best with
FreeRADIUS.

The manufacturers should market small, dedicated, RADIUS server hardware.
Something like D-Link's DWL-2210AP, but dedicated to RADIUS only, without
the rest of the BS in the DWL-2210AP such as the radios. Probably could
even be small enough that it could just be a "module" that you simply stick
into one of your router or AP's LAN ports, give it an IP, and then simply
point the router or AP's in it's direction. The thing probably could be
sold for like $50. (DWL-2210AP is $250, with built-in RADIUS server and
radios.)

....but I guess that would make sense, so I'll be dragging an old computer up
from the basement..