Chick Tracts were little extremist Christian comic books, distributed in the eighties. First, here's the original Tract on the evils of role-playing games. Someone took the same graphics and edited in new text, making a far more interesting version I think. (Thanks phonemonkey for inspiring the Google search that led me to this.)
And on an only vaguely related side note, has anyone tried out this Serenity RPG? It's got several 4 and 5-star reviews on Amazon, and it's a 'verse I'd love to play in, but I'd like to hear from someone who's really played it whether the game's worth the money.