I started a similar thread recently. Here is the link to it...
http://www.yorkietalk.com/forums/gen...nattended.html
At one point, I wouldn't even leave a collar on my dog when I was gone... but this fall I was worried about my younger guy getting cold and was leaving clothes on him. After reading other people's responses on the above thread, I decided it was best to leave my boys naked. The chance of them getting caught up and hurt is probably slim...but because it's a chance, I'd rather not take it. I've been putting my fleece robe on the couch for the boys to curl up in. They love it bc it's fuzzy and it smells like me. I am thinking of getting a heating pad(not a plug in electric one) for them as well.
I know that animals do get caught up, not just from stories, but experience. I've found my cats collar off her at least twice because she got it caught on something. Thank goodness she has a break away collar or else she may have choked to death. Unfortunately, the boys don't have break away collars...so that means they come off when nobodies home.