Let them in the room
before you go to bed.
Okay, seriously -
*Looks around for PETA people*
I have trained dogs and cats by teaching them to fear balloons. I blow up a little balloon, wait for them to get curious about it (that takes about 2.4 seconds for a cat), then pop it then they sniff at it.
Repeat over the next few days until they freak out when they see the balloon being blown up.
Once that fear is established, you can keep the animal away from anything you want by setting a balloon on top of it. I've trained animals to stay off furniture, counters, etc. using this method. After a while, the balloon is no longer necessary.