🚀 go-pugleaf

> ...some idea of how useful a 600-900 pound (still no metric!) payload is?

It's not big enough for most recent payloads, which have tended heavily
toward the pile-everything-into-one-huge-lump school of design.  However,
many people feel that this tendency has gone much too far, and that there
would be many benefits from going back to small single-mission satellites
for a lot of jobs.  600-900 lbs is lots for *one* scientific experiment
plus support equipment, and is enough to be useful for things like
communications and espionage if you are willing to design the equipment
to fit.  Personally, I suspect you could make money on even smaller
payloads if you offered cheap, frequent, short-notice, low-hassle launches.

> 	Would such a delivery system be useful for making small emergency
> shipments to a permanent space station...

Yes, assuming a solution to the unmanned-rendezvous-and-docking issue.
(The OMV now under development might suffice.)
-- 
Man is the best computer we can      |  Henry Spencer @ U of Toronto Zoology
put aboard a spacecraft. --Von Braun | {ihnp4,decvax,uunet!mnetor}!utzoo!henry