Long before optical mice became popular, there was this wooden contraption. It was built by Douglas Engelbart in 1964, and consisted of two gear-wheels positioned perpendicular to each other — allowing movement on one axis. Click here for more pictures.

Long before optical mice became popular, there was this wooden contraption. It was built by Douglas Engelbart in 1964, and consisted of two gear-wheels positioned perpendicular to each other — allowing movement on one axis. Click here for more pictures.