We found 3 Reddit comments about Memento Mori Copper Reminder Coin. Here are the top ones, ranked by their Reddit score.
In Ancient Rome people would say memento mori to generals if they ever got cocky during battles. They had coins with that written on and you can buy one for yourself right here
This is the one I have.
That's what I was thinking too. Memento Mori coins are starting to become more popular with the EDC groups as well as the whole 'modern stoics' trend, but I'm surprised no one has made a two-sided trinket with R. Binum's adage on them. In the era of Etsy and 3D printing, this one seems like a no-brainer!