Yes, I have. I attended one summer at an episcopalian camp, which wasn't too bad. We were required to go to chapel twice a day, but nothing too odd happened. Then I attended three consecutive summers at a camp sponsored by the first assembly of god. The camp part was fun, the jesus part was more freaky brainwashing group-think than the movie portrayed. Kids making out in the woods and then sobbing their hearts out during service, babbling and blubbering and swaying, then leaving service and doing it all over again. What did I take away from it? That religion is messed up, and it followers even more so.