Fisher Space Pens were created in 1965 to defy gravity. No, really!

Originally called the AG-7 (anti-gravity 7), these pens were created to write at any angle, upside down, underwater, in extreme temperatures, and even in the vacuum of space thanks to their pressurized ink refills. They were brought onboard Apollo 7 in 1968 thanks to their extreme writing capabilities, and have been known as the Space Pen ever since.