History of slide-rule wristwatches

Watchismo has a great pictorial round-up of the history of slide-rule and protractor wrist-watches. Man, these things are bad-ass. Link

See also:
Early days of plastic watches Mechanical "LED watch" from 1970
History of calculator watches
Steampunk watch
Belt-drive watch
Watch guts of great beauty
All-plastic watch movement from the 70s
Awesome, impractical, expensive watch