The Casio Game-10 watch, released in 1980 (only 8 years after the first electronic digital watch was released!), let you play a three-line version of Space Invaders : r/interestingasfuck
Casio GAME - 30 original Japan R men's quartz ref.222 digital wrist watch | eBay
Casio Game 10 | Liquid Crystal
Casio Game 10 GM-10 Mod.165 Vintage Japan Digital Watch parts repair | WatchCharts
Casio Game 10
Vintage casio game watch | Game-10 | WatchCharts
casio-gm-10-beige-3 | Vintage Electronics Have Soul – The Pocket Calculator Show Website
Casio 165 GAME-10. First watch ever made with an intrgrated game, all were manufactured between 1980 and 1982. Found it in a bag of other cheap watches in my mother-in-law's closet. :