Cory Archangel reprogrammed an original Super Mario Bros. game for the Nintendo NES system to include only the digital clouds. He's done several other pieces based on vintage video games and clever internet programming.
Ben Fry, "Mario Soup" - click image for link
Other related links include this NES sample art - similar to "Mario Soup"
Also, Ryan Hennessy has been using Nintendo graphics as subjects for paintings like this:
And a hand-painted NES system on eBay