Oddball thought; is there enough room for a simm socket on a Eurocard?

If so you could add a ucLinux simm (http://uclinux.org/simm/), this is a simm
with a processor running Linux, with 8MB ram, RS232 serial port, and 10BaseT ethernet.

Hence hook the RS232 up to the pic (or direct to the empeg), connect the
ucLinux simmm up to a network, and who needs usb :-)

It sounds rather too simple, so I'm sure I haven't thought of something!

Jim