[George from New England]

As Clark Howard says, DO NOT GIVE YOUR SSN to any medical outfit. ANY. Under their medical oath, that cannot deny you treatment.

[glennaro]

Before I came to the obvious conclusions that SSNs are no longer private, I just used a fake one with the following alphabet numbers:
621-31-1920 (6-21-3-11-9-20)

Nobody ever questioned it because they never used it ... they just wanted it.