Not sure if the time I was held at gunpoint by Chinese soldiers counts as a "physical altercation", so I'll say it was the time a "friend" decided his drug problems were all my fault and he headbutted me out of nowhere.
I've always been unable to ignore bullshit from management at work. It's cost me jobs and promotions in the past, but now I work for a trade union, where the ability and desire to argue with bosses is a benefit rather than a liability.
Careful yanks, those bastards will appear from nowhere to fuck up your day, and your front bumper.