Prince of Persia source code
 

I'm not sure if this has already been mentioned here or not, as it's somewhat old news already. Anyway, I learned about it just recently: earlier this year (in April to be more specific), Jordan Mechner had found the source code for the original Prince of Persia for Apple II, which he thought he had lost, and uploaded it on GitHub. Apparently, this also includes game data as well, which might mean a possibility of modern source ports.

The story of how the source was thought to be lost and then eventually found is recounted in Jordan Mechner's blog:
http://jordanmechner.com/blog/2012/04/source/

Here's another article about the event:
http://www.wired.com/gamelife/2012/0...a-source-code/