Pan handlers pretending they will use your money for a good cause. They use pre-recorded bits of conversation but make the call seem interactive. The shpeel is pre-recorded on the callers voice, so they only have to really talk if you interrupt.
Called on 06/18/2013 at 7:21 PM. Left no message. Caller ID says, "SSNFRNCSCO CA." Received a call from (650) 870-9954 on 06.14.2013 with the same caller ID.
Received a call on 06/25 at 5:00 pm. After answering with Hello, I heard a click, and a Hello back. I instantly screamed as loud as I could, hoping to break this annoying habit of them calling over and over. If that doesn't work, I am sure I ruined his ear drums!