When both you and another car facing you need to make a left hand turn at the exact same time on a street and no one uses their turn signals. Usually involves fake starts, flashing your lights, and the unfortunate accident.
Tom: Why aren't you going? She flashed you.
Dave: Nope. It's 2:30 and this soccer mom is faking me out. Watch.
Dave: It's another Left Handed Stand-off.