... but it may not be as useful as you expect.
well, for the period of not spending from a given address, that could be useful
i've been thinking about it lately, because we are going to print bitcoins on paper and let them circulate as a party gig. (a hacker space opening party). using the QR code you'd scan from the paper and receive the address compliant with the bitcoin convetion. a block chain examiner would answer a request to see if the balance of that paper bitcoin is any. there should be at least 1 answer, receiving bitcoins to that address
unless you'd scratch the part with pvt and pub key you would not be able to spend it, but you'd see if it is still valid (i.ex. the issuer did not spend it for you) or if some didn't increase it's value (you would see all transactions, also incoming transactions past the issue date).
if it's a home business or a bitcoin savings account, before first spend it should be a valid observation.
^^ this is the first 10 bitcoins to be printed
feel free to check their value and follow changes in time.
the party is next w-e. with more sponsors, the addresses could get more btc.
but yes, once spent (even partially), the remaining amount would be transferred to a new address and all future incoming payments would be sent away as well.