Dale at Faith in Honest Doubt has a post with a video of a woman, shall we say, declining two Mormon missionaries' offer to discuss religion. My late Grandfather used to act similarly; I recall when the Unification Church showed up at his door and introduced themselves, his greeting was "oh,the god damned moonies, eh?". My uncle told me of an incident when Mormons showed up while Granddad was sitting on the porch cleaning his shotgun for hunting season. As they turned up the sidewalk he closed the breech with a loud click and said, "that's close enough, boys".
This led me to ponder talking points for such encounters......
"I'm God, and I don't recall approving your group."
"Is this the devil-worshipping, baby-killing religion? I already have that literature."
"You boys make a nice couple. You should consider getting married."
"Where do you get your clothes? My wife wants me to dress up like that for sex."
"For communion I prefer black cherry Kool-Aid powder dissolved in vodka. You?."
"I have worshipping your god scheduled for three days next week."
If you have the chance, take off all garments below the waist before you answer the door. Vehemently deny your nudity if they say anything.