This guy promised me a $600 "voucher" to thank me for shopping at WalMart.  All he needed was my credit card number so he could put this voucher on my credit card.
The Called ID on my phone said only "Out of area".  The caller sounded like he was from India.  I asked him for his number in "case we got disconnected".  Needless to say, I did not give him my card number.