Celebrity Gun Show

Jessica Biel showed off her incredibly toned arms wearing a speghetti strap tank for a taping of "The Late Show With David Letterman." She clearly works hard, probably benching Justin. (AP)

Cameron Diaz bared her buff arms in a Michael Kors tank at this year's Kids Choice Awards ... it seems to be a common theme here among Timberlake's gals. (AP)

"Mom in Chief" Michelle Obama has women everywhere reaching for dumbbells to obtain her sculpted arms. (Reuters)

Lost star Evangeline Lilly is known for her seriously buff biceps. That's probably better than being known for a bad attitude. Oh wait, she's got that in the bag too! (AP)

Madonna's massively muscular arms are pretty awe-inspiring, not to mention, intimidating, scary and a little disturbing even. (Reuters)

She may be skinny, but Sarah Jessica Parker could still knock you out with a punch from those guns. (AP)

Halle Berry's arms are toned without being too bulky and are just as flawless as the rest of her figure. Geez, we'd really hate her if she wasn't so perfect. (AP)