On my desk right now, sitting beside my ultra-modern gaming PC, there is a strange device resembling the spaceship control panel from a 1970s sci-fi movie. It has no keyboard, no monitor, just several neat lines of coloured switches below a cascade of flashing lights. If you thought the recent spate of retro video game consoles such as the Mini SNES and the Mega Drive Mini was a surprising development in tech nostalgia, meet the PiDP-10, a 2:3 scale replica of the PDP-10 mainframe computer first...