I had a Casio DataBank Telememo 30 watch (was really jealous of its calculator cousin) which let you add names and numbers to it laboriously with a toggle switch on the front face. Freshman year of high school I had a quiz in Physical Science in which I had to write out from memory the first 50 elements. I spent the night before entering them, and double-checking them as I went to make sure I had them in order (used the phone number part for the atomic number), but when it came time for the quiz, I realized I’d accidentally memorized them all in order from all the slow text entry, and didn’t use the watch. It’s about 16 years later now and I’ve never forgotten them. The secret to remembering anything is to use a terrible text input system to write it out.

Credit: gfixler @ reddit