Ellen DeGeneres checks out Katy Perry's cleavage

Chat show host Ellen DeGeneres appeared to be checking out Katy Perry's impressive cleavage as they posed together at the Grammys.

The cheeky glance clearly amused Ellen's wife Portia de Rossi (far left) who couldn't stop giggling. 

See who else has been busted checking out the ample assets of some of Hollywood's biggest stars...