It was Kathy Bates' idea to make David (Michael C. Hall) imagine everyone in the church naked.
At Hanna's, Gilmore Girls is on the T.V.. Peter Krause, who plays Nate Fisher, was in a relationship with Lauren Graham, who plays Lorelei Gilmore.
When Claire Fisher says "Why is everything acting like I'm in the Trenchcoat mafia" is a reference to Eric Harris and Dylan Klebold, who were the perpetrators in the Columbine High School massacre of 1999, and were thought to be members of this gang for some time.
When Claire and Ruth visit Hannah's house, they all watch Gilmore Girls. On the show Gilmore Girls, Cristine Rose (Hannah) plays Christopher Hayden's (Rory's dad) mother in two episodes.
Claire (Lauren Ambrose) says "I'm not Jeffery Dahmer, I don't get off on hacked up body parts". Dahmer was an American serial killer, who murdered at least 17 males, and was a cannibal and necrophile. In 1994, he was killed at age 34 by a fellow prison inmate.