Planning Ahead

Recently I started thinking about the internet and people who spend a lot of time there. What happens when that person dies? Does the family know how to notify the online community? There is a blog I follow which hasn't had a post in over two months. What if that author has passed on?
Last night I sat down and thought about every website, username and password I use online, and I wrote them all down in a notebook that I keep by the computer. I've showed my wife what it is and where I keep it. If anything should ever happen to me, she can access all my websites, user accounts, etc., to let friends, vendors, facebook users, etc., know that I'm gone. Something to think about.