We had a scare here.  I got a new quesadilla maker and it came in a
pretty flimsy cardboard box.  We put the box on the floor for Oliver to
enjoy.  Not only did he like hiding in the box but he was tearing pieces
off.  I didn't stop him because he wasn't eating it just making a mess.
 At one point I looked over at him and realized he was distressed.  He
was pawing at his mouth and looked very rigid.  I thought a piece of
cardboard had become lodged between his fangs but when I tried to clear
his mouth I couldn't feel anything.  I was amazingly calm when I told my
husband "we have an emergency" and I picked Oliver up.  By this point he
was very rigid and his front legs were doing this weird thing in front
of his body.  It was like he was trying to hug himself.  I wasn't sure
what to do so I first tried squeezing his sides a little.  Poof, out
popped a piece of cardboard.  It was nicely rounded and probably worked
as a perfect cap over his gullet.  I don't think he was trying to eat it
(it wasn't chewed at all) I think he accidentally got it too far back.

For about 30 seconds Oliver was all loving and cuddly but then he jumped
down and looked at his sides and noticed I had ruffled his fur.  I got a
glare and he started smoothing things over.  He was none the worse for
wear but Meowmie needed a drink!  This just reinforces why I don't let
either of my boys play with stuff like that when I am not around.  And
needless to say, no more cardboard that can be ripped up!