Received a call from 706-789-6543, no caller ID ("unavailable").  The pre-recorded message left on my answering machine indicated that the caller was selling final-expense life insurance.  But the message kept asking questions and interpreting the silence that followed as valid answers.  Typical examples:

    "Would it be okay with you if our specialist calls you back?  [silence]  Great!"
    "May I have your first name please?  [silence]  Thank you."
    "May I have your last name please?  [silence]  Thank you."
    "What's your favorite hobby?  [silence]  Great! Thank you."

For all I know, this may be one of those scam calls where they record your voice and later use it to claim you agreed to buy something.  A lot of that going on now.