"Pete Townshend at his best is completely silent."

That works pretty well, especially when someone is on the phone to you with some kind of grievance against you. Just don't give the grunts and the little sounds that indicate you are listening. Just listen in total silence, and when they say "Are you there still?" you just say "Yes," and stay silent. Drives em crazy.

And face to face you can do the same, just don't give the body language nods and that. When you do it to someone in authority that's called "Dumb Insolance".