DIY: build a NASA Apollo Landing Computer

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John Pultorak, who is a 54 year old Lockheed Martin software engineer, built his own Apollo AGC in his basement. He completed it in 2005 - it took him 4 years to build it (working about 10 hours a week on the project) and he spent about $3, 000 for the required hardware. When finished, he created a fantastic 1,000 page documentation which includes detailed descriptions and all schematics of the computer.
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The Apollo AGC itself is a piece of computing history, it was developed by the MIT Instrumentation Laboratory and it was a quite amazing piece of hardware in the 1960s. It was the first computer to use integrated circuits (ICs), running at 1 Mhz it offered four 16-bit registers, 4K words of RAM and 32K words of ROM. The AGC mutlitasking operating system was called the EXEC, it was capable of executing up to 8 jobs at a time. The user interface unit was called the DSKY (display/keyboard, pronounced "disky"); an array of numerals and a calculator-style keyboard used by the astronauts to communicate with the computer.
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By the way, when Neil Armstrong and Buzz Aldrin landed on the moon they did have some trouble with the AGC which reported several unusual "program alarms" and guided them towards a large crater with rocks scattered around it.
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