korea website said "yes". You can leave words there, in order to send them to the people related. You can also leave will there. People will remember you via your words or they will no be hurt.
But there are two questions:
(1) One way there is to require you to reply once per month to confirm you are alive. Isn't it weird? If you have a holiday where you will no go Internet and you forget to tell the website, then they will consider you are dead. Wow, terrible.
(2) How they will confirm the validaty of the words? Especially to the will. Is the one stored in the website having same legal power with the one stored in your lawyer? If there are some difference, what will happen?
Anyway, it should be interesting to try, as we still have so many words to say after we die.