Celebrity Underboobs Guess Who!

Can you guess which sexy star gave a lil' sneak peek of underboob in this eye-popping shot? It's Thirsty Thursday indeed, so sip up our clues and see if you can score the unknown celeb ...

She may be a big celeb from Canada, but she's still a pretty little liar ... You can tell from this smokin' shot that she's a fashionista -- so much so she was a guest judge on "Project Runway."