"Space Travel" (1969)

Ken Thompson's 1969 computer game, where players pilot a spacecraft through the solar system, never achieved the kind of fame that the similarly named "Spacewar!" had earlier that decade. But his creation would later play a role in the software that powers one of the most popular consumer devices ever: the iPhone.

Dennis Ritchie, who is pictured here with Thompson, helped create versions of "Space Travel" for other machines besides the Multics operating system. Together at AT&T's Bell Labs, they created Unix as a direct result of work on "Space Travel," according to an article by Ritchie on Harvard University's website. Unix underpins Apple's Mac and mobile iOS software today.