Moo (later marketed as Master Mind) was an import from Cambridge. A
moo leader board sprang up. Maintenance of a file that had to be
written on behalf of any user posed a conundrum--how could you protect
it against false updates? Dennis's novel solution to this and related
problems was setuid, which garnered the only Unix patent.

Wumpus was my preschool kids' introduction to computing. They learned
the tricks of shooting crooked arrows faster than I learned that the
cave is always the same, with random room numbers. Only years later
did I discover by reading the code that the shape is a dodecahedron.
That fact would have helped note-taking a lot.

Doug