[WalterSear]

* An anonymized reputation system is the equivalent of a transaction ledger. It needs no external source, as long as the involved actors agree to enter into evaluation of each other.

* Digital assets ownership ultimately only require external sources of truth for storage of whatever digital asset they intend to provide. I concur that this would be impossibly expensive to provide via an existing blockchain implementations, without an external point of truth, but still a technically possible feat.

* An entire company on the blockchain? Sure, it's not reasonable at the moment. It was just an attempt to paint a bigger picture. The fact that it's 'not yet reasonable' is why many people are starting to try. By the time it's 'reasonable', someone will have done it.