Another project that makes me go, "Wow!"  Basically this reads the luma signals coming off of old computers or video game systems and with the help of another board allows them to be converted into something that can be output to HDMI.

LumaCode is an interface standard for transfering digital video data from retro computers. Its main application is to be used for machines that do not already expose the video signal in a digitally usable form. Because of its simplicity, the necessary hardware to generate the LumaCode signal for a specific machine can be made quite cheaply. The main effort to translate this signal to something to be used for an actual monitor or TV can then be done by an external upscaler. This upscaler is probably more expensive but can be shared by multiple retro computers.