If you’ve never heard of the old Home Brewed Computer Club, look it up. This was a group of hobbyists that met in the 1970′s to discuss and build their own computers around the new technology of microprocessors. Among the results was the original Apple computer. Of course, I was way too young to have ever participated in that group, but the idea of building a computer rather than just assembling one is very exciting to me. As it happens, Make: recently linked to an article about a British home-brewed computer, the Chaos computer, which I found quite interesting:
"The computer described on these pages was started in 1977 with the gift of a Signetics 2650 microprocessor by Mullard. Attempts during the previous year to order an Intel 8008 and a 2650 from Farnell had all proved impossible, and this 2650 processor was finally obtained after my father drafted me a letter which I sent to the Managing Director of Mullard. The 2650 was an 8 bit processor with 32Kbyte address range and 256 I/O locations. It has 7 general purpose registers and an on-chip return address stack for subroutines with 8 entries. It was not possible to make data access to this stack or flush it to memory. "