A programmer has painstakingly converted the schematics of Computer Space into FPGA code. FPGA stands for Field-Programmable Gate Array and is essentially a way of turning hardware circuitry into software so the closest match to how a circuit is designed can be tested and run without needing to assemble the diodes and resistors.
Click this link to see a video of the work of Mattias of FPGAarcade (currently moving to a new web hosting provider) who has created Computer Space out of software in a form that most closely matches how the hardware circuit boards perform. Mattias approached myself for sound clips so the sounds you hear in his video are captured from my own unit.
A detailed description of Mattias'es progress is readable here on the KLOV forums. You might need an account to log in and see the thread.
And a two-player version has even been created recently. Click the image below to see footage from YouTube of the game.