dead man switch has also been discussed - it would be activated if there is no activity(outgoing transactions?) for some amount of time...
Just remember:
You could easily be hit by a truck today: No time to tell anybody about your secret stash of Bitcoin stamped on a piece of metal buried in your garden. No time to tell anybody the password to your bip38-encrypted paper wallet.
Where it is nice, that your Bitcoin are safe from the government and banks, it would be really sad, should you suddenly die and the Bitcoin are just lost, instead of supporting your own children.
So, I am less interested in theoretical ways to solve that problem, but more if somebody here actually did something to solve it.