When I first got married, my wife had the irritating habit of telling these people to come back and talk to me, and telling them when I'd be in. One day she told me about two guys from the Church of Jesus Christ. So I asked a few questions, they were two white men in identical natty American-style suits, so that had to be the Church (mumble) Jesus Christ (mumble mumble mumble) AKA the Mormons. So when they came back, instantly recogisable for what they were as the uniform is very distinctive, I said 'Ah, you're the Mormons.' You should have seen the look of amazement on their faces. 'How do you know we're Mormons?' So I explained. They were gone in 30 seconds, and never came back.