> are there any business users who use it to backup an entire organisation's systems?
Stripe has been a happy Tarsnap customer for several years. It's robust and thoughtfully designed, Colin has provided great support, and "backups for the truly paranoid" is a pitch that very much resonates with us.
Definitely vault physical backup copies of private key material at a physical safety deposit box in a bank. Preferably two copies in two banks in two different timezones.
