In 1958, Tennis For Two went on exhibition at the Brookhaven National Laboratory in New York. With controllers and an analog display, it's regarded as one of the first ever true video games.
The original Tennis for Two was only on show for two years before being dismantled in 1959, used primarily as a novelty for the lab's visitors. Wired reports that thanks to the work of a present-day team from Brookhaven, it's now almost back in action.
While an attempt was made in the 1990s to restore the game, it cheated and used more contemporary electronics in parts. This version, however, is shooting for complete authenticity, right down to the computer powering the whole thing.
As a man who loves history as much as he loves video games, this is awesome. Hopefully when it's done people can get the chance to play it!