I was talking on the phone with my cousin today. She has worked as a
substitute teacher in several schools. She is between jobs. One of
the things she mentioned was that they require her to furnish her SSN
on job applications. Since the wrong person could do some serious
damage with your SSN, I really think it is a bad idea to have to
furnish them for a job application.

I went online tonight to put a hold on a book at the library. The
library is using the first 4 numbers of my SSN in their "primary
identification" field.

That seems like a violation of security to me.