<2)Let's take the GRiD server as an example (I have never seen a GRiD < machine, BTW). How does it differ from any desktop system? Too broad a question. What is a desktop system? I can come up with several that might surprize you. <3)Have there been any machines that made extensive use of a truly < unusual architecture? What I am looking for is twofold: I am < interested if anything ever used a neural network-like arrangement, < and I am interested in something that had a processor that < interacted w/the user and a separate one to do the processing < (ie a real-time system capable of doing all that a normal one can) IS there one or three questions in there? yes there have been some very unusual machines like transputers, connection machines, vector processors, Turing machines. the latter half of your question is too broad. My z80 s-s100 crate would qualify as the OS was distributed over several z80s but only on had the user interface. The Vax-11/780 had a qbuss PDP-11 as a diagnostic fromt pannel. An xterm on an eithernet to a server could even qualify. Allison