Stating the problem thus makes it intractably hard. Look at it from the other side: you will die one day, and you need to make preparations for your death that include your online possessions and presence.
I keep a list of passwords and instructions with my will. That's all there is to it. Think things through once and you never have to do it again.
I got stung by this last week - a "low grade common" password I used on perlmonks.org which I didn't care much about was the same password I used when I signed up for this new website a couple of years ago that I didn't care much about at the time ... called twitter... Fast forward a year or two and I hadn't bothered changing the twitter password and a few days after the perlmonks incident became public I start getting spam posted to my twitterstream... Grrr...
(and, in the cleanup job I did I found 56 other websites of varying degrees of "care about" that I was using the same password on...)
I still haven't decided how much effort to put into ensuring this doesn't happen again - individual passwords for every website is _doable_ but the convenience tradeoff is not insignificant... (anyone know a password safe type program that runs on Mac, linux, and iPhone, and will sync databases between the three?)
That I can never understand. I'm a control freak. I'm a spider, and I'm not going to let a small thing like death limit the reach of my web. (muhahahahahaha..)
I am accomplishment-oriented rather than experience-oriented [1], and perhaps a lot of folks on HN are the same. I derive daily motivation much more from having a sense of accomplishment and impact on the world, than from experiential pleasures, or even from having learned something. If you feel the same, it behooves you to think about the impact you will have on the world after you're gone, and how to best channel it. It's only experience that ends when you die.
[1] Citations please? I remember reading something like that dichotomy, but I can't find it.
I keep a list of passwords and instructions with my will. That's all there is to it. Think things through once and you never have to do it again.