The Computer Hack That Saved Apollo 14

Apollo 14 almost never made it to the lunar surface thanks to a hardware failure which caused a short circuit in the abort switch. With the computer seeing the abort switch enabled the software team back on earth had a limited amount of time to figure out how to make the computer ignore the erroneous signal while still performing the landing. This required tweaking program state in memory while the program was running, a delicate operation with dire consequences for failure. No pressure guys.