Back in the good old days before answering machines, if I picked up the phone and the other party said "Mrs ..." that was the dead giveaway that it wasn't anyone who knew me.

I then proceded to start the Feminism 101 lecture, and the phone manners lecture (you DO NOT assume the identity of the person who picks up the phone) which could go on for hours. Usually they hung up on me. HA!

Somedays when I wasn't in Didactic Mode, when the telemarketer said "Mrs. His-Last-Name?" I simply said No and hung up the phone.