Ahh. Hee, I never thought of using them that way. Prolly because for one, I usually sleep in my clothes. (Don't ask, I'm lazy.) For two, here in Western MA you sleep nude or near-nude in the summer to keep from sweating to death, and the rest of the time you bundle under a million layers of clothing to keep from freezing to death. (There's an e-mail joke floating around that claims, among other claims, the general sentiment of "You know you're from Western MA when your idea of sexy lingerie is flannel pajamas.")
Peace & Luv, Liz