My mom left behind some number code
Just for fun, it would be cool if each of us remembers to take the time to leave at least 1 or 2 little puzzles for our descendants to figure out, as a way to have happier feelings again one last time with you, in a way.  My grandpa would totally have done something like this.  I remember he showed me a big book of unsolved lost locations of buried treasure, and a related story he read me about a golden key hidden behind a wooden tile of Key West, FL in a large, painted wooden wall map of that part of the ocean.
I'd totally love to leave a little puzzle for those I love.  Maybe we could all try to remember to do so, or do it now way in advance by setting up cloud compute accounts running a script like a time capsule that will send out certain messages at a specific date in the future.