My dojo has actually had problems because of this kind of thing. We can terrorise a room by sitting in corner reading a book, practically.
We can walk into a bar and the place goes silent and everyone just stares at us. It's like a scene from a western when the gun slinger walks into the saloon.
There's a book with a nice quote - I think it is Forest Morgan's "Living the Martial Way", but it may not be.
The author talks about going into bars and getting into fights all the time. Then realises that he goes in and sizes up all those present subconsciously, thinking "I could take him, him, ....".
Things get more peaceful when he goes in to bars with the attitude "everyone in here is safer because I am here..."
Then of course there are all the stories of zen masters playing with tigers etc as opposed to fighting them...