there is this software you can buy that will flash your radio to a different software and allow you to do stuff like watch videos or play video games while driving.
http://www.searchamateur.com/product/Power-Play-TV-Games.htmI don't know exactly what I would use that input for. though you can still play cool games on it for the passenger when on a long trip. I remember this controller I bought either at a flea market or a mall and it has a cable (yellow, white, red) and you can play a bunch of little games on it.