Yeah, I do!
I have two different phone numbers (one regular, one for fax) and after the 2nd bottle of wine, we dialed the phone number of friends who don't like each other - a guy and a girl - simultaniosly and connected the receivers upside down, so they could hear each other and talk to each other.
The girl was the first one to answer: "Hello, who's there?"
After a few seconds the guy answered his phone: "Hello?"
Girl: "Yes, who's this?"
He: "John, and you"?
Girl: "What do you mean "you"?"
He: "Huh"?
Girl: "What do you want?"
He: "Nothing. You called!"
Girl: "What's that supposed to mean?"
He: "You called ME, so what's up?"
Girl: "No, no, YOU called me! "
He: "Why would I do that?"
and so on, and so on......
We had a blast with that one for a while