Before there were Infocom games we had the Choose Your Own Adventure books. Better than reading a story from beginning to end, these books allowed the reader to make decisions at key plot points that affected the storyline. It wasn’t quite immersive, but came closer than Pong. These books–many of which I still have–did nothing to quell my latent obsessive tendencies. After an initial “organic” read, I would go back to the start and methodically mark each fork, following each possibility to its end before heading back to the most previous fork. What’s past is prelude. Rainman would have been proud (albeit in a detached way).