Original Prince of Persia Source Code Released for Free
In 1989 a young game designer called Jordan Mechner took a bunch of pictures of his brother jumping around the backyard, rotoscoped them and made the original Prince of Persia for the Apple II, the first game in the sub-genre of platformers called “the cinematic platformer” (according to Wikipedia, at least). After the game was released Mechner apparently lost the floppies which contained the original source code for the game. Well, they aren’t lost anymore.
Over two decades after losing the floppies Mechner has found them in the back of a closet. With some help from Jason Scott of textfiles.com, Mechner recovered the source code and has released it into the internet for free. You can download the code over on GitHub and get to fucking around with it.