There are a few services that can provide you with "disposable" email addresses like Spam Gourmet, and even one or two for disposable phone numbers (eg Numbr). They're useful for when you need a genuine email or phone number, but you don't want it to stay valid forever. For instance, when you're using your email address to sign up for some websites, it's nice if that address becomes meaningless after a week so they can't spam you.
The idea could be extended further, too. Some services (American Express, for example) offer disposable credit card numbers to avoid fraud. It wouldn't take too much to set up disposable postal addresses via post office boxes or coded addresses at a proxy company. It would be harder to have a disposable physical drop-in address, though that could be done with a large building that rents out cubicles for very short periods.
Past there it gets a bit philosophical. Could you have a disposable name? You'd have to answer to it for a while, but then you just aren't called that name any more.
Mokalus of Borg
PS - Disposable birth dates? Disposable mother's maiden name?
PPS - Those are almost completely meaningless.