It already has, to a small extent. Two services I can think of which already aim to provide this guarantee: Firefox Sync [1] and Tarsnap [2]. [1] http://docs.

It already has, to a small extent. Two services I can think of which already aim to provide this guarantee: Firefox Sync [1] and Tarsnap [2]. [1] http://docs.services.mozilla.com/sync/overview.html#cryptography http://docs.services.mozilla.com/sync/overview.html#cryptogr... [2] http://www.tarsnap.com/crypto.html http://www.tarsnap.com/crypto.html