I am not in the exact same situation as you (I work as an independent developer and have several clients), but here's what I did - I made an agreement with a fr

I am not in the exact same situation as you (I work as an independent developer and have several clients), but here's what I did - I made an agreement with a friend / previous business partner (who has similar development skills to me) that each of us would be the 'emergency stand-in' in case of illness / death of the other. Our agreement covers short-term maintenance of applications, and negotiating with the clients to find another 'full-time' person. We have shared passwords / information about SVN repositories / assembla spaces and so on, but it would also have been possible to leave this information with a lawyer and only have it made available to the other person if necessary (in case the clients are nervous about someone else having access to 'stuff' without need). The chance of both of us being 'out of order' simultaneously not so significant (we currently live in different parts of the planet, so the 'team bus' situation doesn't apply), and this agreement was welcomed by all our clients as it provides a good layer of safety from their point of view. This arrangement is not perfect, but - based on trust - is 'free' and extremely reliable. If you don't have a friend you can rely on in the same situation, perhaps you can find someone in the same tech circle (or via HN?) and then go the 'you get all the necessary info to continue on EXCEPT the passwords lawyer way'?