Whenever its someone calling from out of the country trying to sell my parents something, after they start talking and I recognize its a forienger, the discussion goes soemthing like this
Telemarketer "Hello! Did you know that you are eligible for a phone upgrade?"
Me "Thank god you called!" then I move the phone away from my mouth and say "ITS DELL TECHNICAL SUPPORT THEY ARE GONNA FIX OUR COMPUTER!"
usually they hang up right there.