My cats literally knock on my bedroom door if it's shut. We're not talking a light tapping - they've figured out how to make it sound as if a big burly man is actually outside the door banging on it. Also, Sophie has this toy - a string attached to a stick - she likes to bring it to me in the middle of the night while making the worst noise known to man. I've never heard another cat make a noise that sounds anything like this - it's almost like she's bringing me "her kill". Silly cats.
