Because as we answer issues of cost and availability, a logical thing to wonder is "how long can I really depend on it though?" As quickly as cloud services (where "lifetimes" are measured at six years) have entered our economy, that's a question begging to be answered.

Amazon at least seems to be an "eventually durable" datastore, though. Meaning that if you are told in the future that it will go offline, you have an excellent chance to make other suitable arrangements. Say there's a 0.01% chance of this product being discontinued next year, up to a 10% chance 5 years from now. I have to think there will almost certainly be other services you can move your data to, on similar terms, for a long time.

That's assuming you're around at all, and nothing reeeeeally bad happens even so. Making data last after your death (or even after you stop paying!) is a lot harder in this environment, and achieving true 100-year durability is a tough nut indeed.

I like your bank idea, since the preservation of a bank account is just a specialized simple case of data preservation. Data preservation seems rather more reliable when the data is directly attached to money. Then again, maybe banks themselves are on their way out for this purpose — Dropbox could become the new safety-deposit box.

But there are 100-year domain registrations, after all. Maybe we're ready for organizations to at least offer 100-year storage, too.