Braunstein, the world's first role-playing game

Most gamers have never heard of Braunstein. Sad but true. In the
hierarchy of self-awareness you’ll find the circle of gamers who know
what D&D is (a very, very large circle), then inside of that is the
circle of gamers who know what Greyhawk is (large but smaller), and
inside that the circle who knows what Blackmoor is (smaller still). And
then in the very center, vanishingly small, are the people who’ve heard
of Braunstein. Which is a pity, because Braunstein is the granddaddy of
them all. (Metafilter)