It's not the sexiest gadget on the list, but the Hewlett-Packard HP-65 was touted as the "smallest programmable computer ever" in 1974. You could run programs that consisted of up to 100 steps. The HP-65 came with 51 built-in functions and operations, as well as a tiny magnetic card reader and recorder. You could store programs on magnetic cards or use preprogrammed cards containing a variety of programs used in numerous disciplines. The HP-65 also became the first programmable handheld calculator in space when it was brought on as a backup to the Apollo Guidance Computer during the 1975 Apollo-Soyuz Test Project.