Well maybe it wouldn't be efficient, but a million Apple IIs networked together would make for the most awesome supercomputer ever.
Desmond: There are probably a million of these, scattered around in people's attics, garages, and basements! Do you know what kind of computing power we'd have if we put them all to work?
Geordi: About the same as one iPhone?
Desmond: ... I suppose so.
Geordi: But they'd use a lot more electricity.
Desmond: I hadn't thought about that.
Geordi: Just cooling them all --
Desmond: Got it. Thanks.