Usually I wouldn't come here for medical advice, but I was just thinking about whether sleeping on the floor (carpeted or hardwood) causes any major health problems, and for once, Google has let me down. I actually prefer to sleep on the floor occasionally (with a pillow), and it doesn't usually give me back pain. Sometimes I'm a little sore, but I stretch, and I'm fine, and I'm sore on my regular spring mattress sometimes anyways. So anyone have any personal experience or knowledge about whether it's OK to sleep on the floor? Links appreciated. Thanks!