> I'm a little unclear on what problem you're trying to solve.
So am I, actually, sorry. My initial thought was that a central authority (a host that might go down or bankrupt) could be avoided if I were to split my secret into parts, distribute them among my loved ones (telling them what it is about and that I trust them they'll not meet behind my back while I'm still alive), accompanied by instructions how it works. This way, there's no plain text of my super secret stored anywhere.
This solves the "my secret should be known by my peers when _something happens_"-issue. The "inform the others if something happens to me"-problem actually persists and for _this_ problem, a service like the one posted probably is a solution, sending out "the person has not been reachable for X days, please meet and uncover his secret"-mails to the peers.
You could setup a scheme where just X (but no less) out of all Y (partial) secret holders are enough to recover the secret. There are cryptographic schemes for that.
Simple way might be to just use overrepresented[1] error correction code like Reed-Solomon where it'd only take half the parties to reconstruct the full message. Should be fairly easy to set up using par2 utilities right now actually.
[1] I'm fairly certain there's a real word for this, but I cannot think of it, anyone else know?
Assuming the number of parties is fixed (and it would have to be, wouldn't it? I don't see how the question could make sense otherwise), this is still more complicated than necessary. The general term for this is "secret sharing" and there's a really simple method for it, known as Shamir's Secret Sharing.
Sounds like what Tahoe-Lafs does - uses the ZFEC (another FEC algorithm, like Reed-Solomon, but much faster) library to let you specify how much redundancy to generate; you can have 2-out-of-3 or 3-out-of-9 or other ratios.
So am I, actually, sorry. My initial thought was that a central authority (a host that might go down or bankrupt) could be avoided if I were to split my secret into parts, distribute them among my loved ones (telling them what it is about and that I trust them they'll not meet behind my back while I'm still alive), accompanied by instructions how it works. This way, there's no plain text of my super secret stored anywhere.
This solves the "my secret should be known by my peers when _something happens_"-issue. The "inform the others if something happens to me"-problem actually persists and for _this_ problem, a service like the one posted probably is a solution, sending out "the person has not been reachable for X days, please meet and uncover his secret"-mails to the peers.