I had my first door knocker as an Atheist. I was a bit disappointed, because they didn't knock loud enough to wake me up. They left there literature between my doors and left. I wanted to see there expression on their face when I told them im an Atheist. Even tell them to fuck off if I had courage to do so. I tore the dogma up and pitched it in the trash. Which was kind of a thrill.
Eh, I get no kick out of being mean to the door-to-door religion salesmen. I've found that most of them think they're doing a good thing - they're obviously wrong, but wrong can still come from a good place. I don't entertain their nonsense, but I've found that a good "thanks but no thanks, have a good day," works as well as anything else. Plus, it doesn't foster the already prevalent misconception that atheists are a bunch of assholes.