Our company is working on such, but a much more advanced solution with possibilities to encrypt such data-on-the-go and more..
Very soon more available at
RealIdent ; where you'll be able to store any bit of data you'd like; as long as it's not binary (to start with).
The Yubikey is the perfect solution for access to such storage; where not only users will manage & have access to their content; but also API developers will be able to store their bits/read public data of their users.
I'll be posting more about this "online vault"; in the meantime i'll be programming for the remaining weeks to get this product up-and-running ...