Probably too late, but, someone once called me and asked, "My computer screen is all 'squiggly', can you fix it?"... I went down to see what the problem was and removed the magnet she had placed on top of the monitor. "You are such a genius," she said.
At a meeting in which all present only speak English, offer your questions or answers in High German and enjoy the deer in the headlights look from everybody. Don't grin until you leave the room though.....