LOL I had a telemarketer that called me on the phone once and I interrupted his pitch to start in with my sales pitch for products I sell (not over the phone). When he finally said he did not want to buy, I asked him if he could hand his headset over to the guy in the next cubicle so I could see if he wanted to buy something.
Oh, instead of just any number, try dialing random 800 numbers - especially at night. You get some real funny people answering company 800 lines ringing into offices after hours.