Are you annoyed that your cat doesn't do anything but look at your hamster or mouse all day? Here's a way to stop it.

Hope it helps!

[edit] Steps

Get your cat away from the pet. You want to try to get her mind off the animal. Plus, if you can close the door to the room the other pet is in.
Get a few cat toys. Or even make some yourself! Cats really love a piece of string with a tin foil ball attached to it.
Know that once you have the cat toys try to keep her busy(and get her away from the room the pet is in) play with her until she falls asleep or until she's all out of breath.
Pet her and make sure she doesn't keep coming back to the room with your hamster in it.
Take her outside(if she's an outdoor cat) give her a walk, or even introduce her to other neighborhood cats. Just remember if it's an indoor cat don't bring it outside, that's just cruel.
Try to teach her some tricks can i suggest beg or chase your tail? My cat can do those and it's hilarious!
Remember that when it's time for you to go to sleep, close your door where the hamster or mouse is and if the cat starts crying bring her into your room and pet her until she falls asleep!
Hope this helped!

[edit] Tips

One of my cat's favorite toys is a piece of string so you could try that for step number two.
If none of this works move the hamster or mouse to another room where the cat doesn't know about.