Matt Damon, Olivia Wilde, Bono, and Richard Branson are trying to end the world water crisis ... one toilet at a time.

As Matt said back in February when he started the movement, he and his pals "won’t go to the bathroom until everyone in the world has access to clean water and sanitation." New Hollywood A-listers, including Olivia, Bono, and Richard, recently joined Matt's "toilet strike."

The strike -- led by Matt's advocacy group Water.org -- is intended to end the water crisis that has left 780,000,000 million people -- one in nine -- without access to clean water and sanitation.

The stars tried to use humor to lighten the severity of the situation in a new public service announcement.

"I remember when Matt first brought up the idea, it was at a meeting of the Illuminati," perennial activist Bono said.

Wilde joked that Bono was mad that she joined the elite group of celebs involved with the movement, "Bono was so mad. I only got in because I am an android from the future."

Damon closed the video by encouraging others to join the strike. "And remember, if you don't use the toilet, you're a celebrity," he said.

For other information about the cause or to make a donation, visit water.org or strikewithme.org.

It's nice to see that some Hollywood marriages really do stand the test of time!

Matt Damon and wife Luciana renewed their wedding vows in an intimate island ceremony at the Sugar Beach resort in St. Lucia on Saturday, and they had a star-studded guest list to help celebrate the momentous occasion!

Fifty guests, including Ben Affleck and wife Jennifer Garner, watched as the couple swapped sweet words under a thatched roof at sunset. The Bourne actor wore a tan suit and flip flops, while his lady love donned a cream colored gown. Their four daughters Isabella, Gia, Stella, and Alexia were also on hand for the special day.

"This isn't a 'Hollywood' wedding. Matt wanted it to be fun, happy and private. He felt like Luciana deserves this, first and foremost," a source told Us.

The cost for the bash? A whopping six figures!

Lucy is one lucky lady to have a man like Matt!

This promises to be quite the showcase of the male physique!

Matt Damon and Michael Douglas star in the upcoming HBO biopic Behind The Candelabra, which follows the life of famed pianist Liberace, and the actors must be pretty confident in their sexuality to take on such risque roles!

Mr. Damon, who plays the love interest to Michael Douglas' Liberace, admits the sex scenes were more than a little uncomfortable to film.

"The scene where I'm behind him and going at him, we did that in one take. We do it. Cut. There's a long pause. And then you just hear Steven [Soderbergh] go, "Well... I have no notes'," he confessed to Entertainment Weekly.

We have a feeling this going to bring in some serious ratings!

Nothin' like working with your pals!

George Clooney and good friend Matt Damon are currently in Berlin shooting their upcoming movie The Monuments Men, and Gorgeous George is calling the shots while Matty D takes care of the acting!

Hollywood's perennial bachelor co-writes, directs, and stars in the film, which is about the Allied soliders who protected art from being destroyed by the Nazis during World War II.

What we wouldn't give to be an extra on that set!

Matt Damon landed at Los Angeles International Airport on Tuesday evening, and even though his latest flick isn't doing well at the box office, he was in a great mood, signing autographs and posing for photos with a handful of happy fans.

Matt will be appearing on Jimmy Kimmel Live tomorrow to promote Promised Land, and we're not sure if he'll chat about how little money it's made at the box office (so far it's only earned $7,542,000 and it cost $15 million to make), but we're guessing he might address the fact that the film was financed in part by Image Nation, a company completely owned and operated by the oil-rich government of the United Arab Emirates.

The film follows a salesman for a natural gas company (Damon) who travels to a small town to try and buy out land from the locals, but he's met with quite a bit of resistance. Last month Damon was asked about the foreign-oil funding at a promotional event in New York, by Philem McAleer, who directed the pro-fracking film FrackNation. McAleer asked Damon, "How does it feel to be a fully-paid advocate for an oil-rich Middle Eastern government - and doesn't that really negate any artistic credibility that Promised Land might have?" Damon's reply? "[T]he first time we were aware that Image Nation was involved with our movie was when we saw the rough cut and saw their logo."

He's gotta keep that action star physique!

Matt Damon headed to an L.A gym for his daily workout today, and the True Grit star proved he's a law abiding man by feeding his parking meter!

We've caught the hunky actor working on his fitness a lot lately, and we have a feeling it may have something to do with the rumors he's eager to reprise his role in the Bourne movies.

Although the Oscar winner is still searching for the perfect script to make his return to the action franchise, he's clearly getting a head start on making sure his muscles are ready for all the intense stunts!

Lookin' good Matty!

Matt Damon and his gorgeous wife Luciana left their kids at home for a sexy night out at the Promised Land premiere held at the Directors Guild of America.

In the flick, Damon plays a salesman for a natural gas company whose life changes after arriving in a small town.

The sexy hunk stars opposite Frances McDormand in the Gus Van Sant-directed film.

This is why we love Matt Damon!

Yesterday the Oscar winner was snapped at L.A.X., and after hopping off a plane, he spent time signing autographs for nearly two dozen fans who were there to greet him. Later Matt was spotted at the Landmark Theatre after attending a screening of his latest film, Promised Land, and he happily inked even more autographs there.

Matt was still sporting a shaved head for a few re-shoots for his upcoming flick Elysium, but it appears to be growing back out. Thank goodness! We def prefer him with a full head of hair...