I'm a big fan of GOL. It's been proven to be a universal computing machine, meaning it can do anything any computer can do, even recreate all the calculations for Halo 5 for example.
I met John Conway this summer. He hates the game because he considers it trivial, he's done much more important work, and it's all most people know of his work is this game. I think he's lucky to be known for anything!
Got him to sign a couple of boxes of Life cereal. See what he wrote? :-)