The MOM chip seems to be of limited use since it doesn't seem to
be enough expandable: it isn't supposed to be connected to more
than 1) screen 2) keyboard 3) mouse 4) ethernet.
Note however the word supposed in the last sentence. This doesn't
immediately mean that it can't be done. One of us should look over
the MOM chip documentation to have a look if it is possible
to perform some sort of hack. For instance it could be possible
to hook all DMA devices that we want on the connection that's
intended to be hooked up the the ethernet.
Other memory mapped devices might be hooked up to the "general
IO" regions (or whatever they are called), however I don't know
how many address lines there are available.
Next it might be possible to hook other chips to the native
system bus of the R3000, as long as there is no address
conflict with the mappings of the MOM chip.
These possibilities should be looked into by one of us on the
mailinglist. (sorry I don't have time....)