Male agent claiming to work for Visa card services. Had a heavy India accent. His pitch was that he could lower the interest rate to 6% on any Visa card for your lifetime. When I said I didn't have a Visa card only a Mastercard, he said he could lower that one also.
They are bold, they will ask for card numbers, social security numbers, zip code, etc. DON'T GIVE ANYTHING TO THEM! Tell them you have initiated a call trace with the FTC fraud task force. The guy told me "go to hell" and hung up when I told him that.
If you want to have some fun, give them fake credit card and social security numbers. Waste their time so they get talk to less people who aren't as savvy.