Reverend Cedric Miller of Living Word Christian Fellowship Church in New Jersey has banned Facebook. He's ordered about 50 married church officials to delete their accounts or resign and has called on married people in his 1,100-member congregation to delete their Facebook accounts. The problem isn't productivity lost to Farmville—it's adultery.

Miller said 20 couples from his church have had marital problems in the last six months after a spouse reconnected with an old flame on Facebook. "What happens is someone from yesterday surfaces, it leads to conversations, and there have been physical meet-ups. The temptation is just too great."

According to the American Academy of Matrimonial Lawyers, 81% of its members have either used or been faced with evidence from social networking sites in divorce cases in the last five years, including Facebook, Twitter, and MySpace.