this happened to my mom a few years back. she ended up placing literature with the two mormon fellows who came to the door. i thought it was hysterical.
i had a couple of mormons come to my door a year or so ago, and talked to them for a while. it was kind of fun, to discuss "spiritual" things with people. hadn't done it in quite a while. they were somewhat astonished that i knew some things about their faith, as i'd grown up in idaho and montana and it's a predominant religion out there. through the course of the conversation, i told them that i was gay, and their reaction (creepy curiosity) was funny. but i was tired of the discussion by then.