The early video game efforts of the likes of Steve Jobs and Steve Wozniak during their time at Atari, and Bill Gates with his racing/donkey avoidance game DONKEY.BAS, are fairly well-known now, but it turns out there was another future technology billionaire who followed in their footsteps just a few short years later.
As Ashlee Vance detailed in his recently published biography of the Space X and Tesla founder, Elon Musk coded a simple video game in 1984 when he was just12, which he wound up selling to a computer magazine that then published it for anyone else to try (this was when the code for a complete game could be printed on a page or two of a magazine).
Vance included a reproduction of the page from the magazine in his biography and, as noted by The Verge, things took off from there. Google software engineer Tomas Lloret Llinares ported the code to HTML5 and put the game online yesterday, giving it a newfound - and much larger - audience more than 30 years later.
As you might expect, the game, called Blastar, is a fairly simple one - even by early '80s standards - but it does hint at the ambition of the young Musk, and a seeming eagerness to try new things, which he'd of course go on to do on a significantly bigger scale.