Summer/Beach

Ryan Phillippe is suddenly looking JACKED on South Beach, and you can bet he's getting a ton of stares from the ladies -- and also possibly some gentlemen.

But only because he's their "th-inspiration." Yep, that's the only reason.

Joseph Gordon-Levitt hammed it up outside his trailer during a break from shooting his latest movie in Montreal.

Will Smith and Jada Pinkett Smith took their tight, toned bodies to the beach today in Hawaii -- proving once again ... Jada is the hottest 42-year-old mom in a 2-piece.

Mr. & Mrs. Smith had something for everyone -- her toned ass barely covered in a bikini ... and his ripped arms in a tank top.

If you're impressed -- you're not alone. 13-year-old Willow was there too ... and looked pretty awestruck by her parents' ridiculous physiques.

Will still rules in Summertime.

Oscar winner and future "Star Wars" star Lupita Nyong'o showed off her picture perfect bikini body this week while walking along the beach in Maui.

"Bad Girl Club" star Natalie Nunn saw the butt photos of Bradley Cooper and Jennifer Lopez and laughed ... then broke out this thong while partying on the beach in Miami on Thursday.

One can only assume Mama June just discovered water ... because while Honey Boo Boo played around in the pool with her usual youthful exuberance ... her mother swam around WITH HER SOCKS ON.

The Thompsons hit up a pool while on vacation in Panama Beach, FL. According to the photog who snapped the pics, Mama June swam about 30-40 laps in the pool ... never removing her socks.

Soon-to-be divorcée Katharine McPhee did a little advertising on the beach in Cabo this weekend ... showing off her tan-lined body less than two weeks after pulling the plug on her marriage.

As TMZ first reported, McPhee said in her divorce docs she and hubby Nicholas Cokas were separated for seven months before she was spotted locking lips with "Smash" director Michael Morris.

Nicole Scherzinger did her best Jessica Alba impression over the holiday weekend, showing off her incredible bikini body aboard a yacht in St. Barths.

At 35 years old, the former Pussycat Doll still has several lives left in her.

Justin Bieber luxuriated on a yacht in Monaco Saturday.

Bieber looked more ripped than ever as he took a break from the Monaco Grand Prix, kicking back and drinking a brewski.

As we reported ... sources very close to the singer tell us he's off Sizzurp ... in no small part because it screws up his workout routine. One source very close to Biebs says in the past 3 weeks he's been like a different person.

Cutting out Sizzurp ... it does a body good.

Whether it's a modest little dinghy or an insane yacht -- these celebrities taking to Instagram and are bragging about shoving off and soaking in the sun is style... Check out which stars strapped on their sea legs and hit the open waters in style!

Ahoy!