Celebrities know they look good, and they obviously know other stars look good too.
On numerous occasions, photographers have snapped priceless shots of Hollywood's elite checking out their famous friends -- whether they're getting a glimpse at someone's breasts, legs, butt, etc.
But come on, can you really blame Ellen DeGeneres for checking out Katy Perry's cleavage during the 2013 Grammy Awards? Yeah, we didn't think so.
Check out these stars who've taken a peek at other celebrities' assets.