Happy Pi Day!

March 14 — a.k.a. 3.14 — is Pi Day, a celebration of the ratio of a circle’s circumference to its diameter. Many honor the mathematical holiday with wacky traditions, from foodies ironically indulging in pies — even the pizza variety counts — to MIT announcing acceptances to freshman applicants.

But how do you celebrate the wonder that is pi in true Hollywood style? By looking back at blockbusters that have put math on the big screen.

From Good Will Hunting to A Beautiful Mind, relive some of the most noteworthy math-minded flicks in Celebuzz’s gallery.

Then weigh in: What is your favorite math movie? Share in the comments.

Celebrity photobombs, the gift that kept on giving in 2012.

From One Direction to Justin Timberlake, no star went unscathed in the art of photobombing these past 12 months.

Whether you laughed at Jack Black and Dustin Hoffman sneaking up behind a glamorous Angelina Jolie at the Cannes Film festival, or pondered with bewilderment at Lady Gaga‘s menacing stare down with Katy Perry  — there was no denying Hollywood’s sudden fascination (or, in some cases, participation) in jumping behind the camera for a candid moment.

But, despite the number of funny photos captured this year, there can only be five of the very best. Who exactly are they, you ask? Watch the video for Celebuzz’s countdown!

Which celeb had the funniest or oddest photobomb in 2012? Sound off in the comments!

Who knew Dustin Hoffman was a One Direction fan?

During the British boy band’s first-ever appearance on the Late Show With David Letterman – which will air on Friday – the lads sat down with the late night host and his previous guest Hoffman, who got a little too excited sitting next to the teen idols.

The Oscar winner planted a surprise kiss on 1D’s Niall Horan, as Horan’s bandmates — Zayn Malik, Louis Tomlinson, Liam Payne and Harry Styles — looked on in amusement.

According to reports, One Direction performed “Little Things,” the second single off their No. 1 album Take Me Home, on the iconic late night set. It was the first appearance for Simon Cowell‘s pop phenomenon, who are currently enjoying a meteoric rise to fame after their sold-out concert at Madison Square Garden this past Monday.

Since arriving in the Big Apple, the lads have been on a whirlwind promotional tour for Take Me Home, which dropped in November. However, that doesn’t mean Styles hasn’t had time to spend time with his new girlfriend Taylor Swift.

One Direction appears on the Late Show With David Letterman on Friday, December 7, at 11:35PM on CBS.

Cloud Atlas isn’t the biggest box office disappointment ever, but it’s definitely its cousin.

This past weekend, the ambitious sci-fi epic finished number 3 at the box office, opening with $9.4 million. Budgeted at $100 million, Atlas is hard-pressed to make back its money.

Here’s a quick look at more big-budget films forever stuck in the red.

1. John Carter

Production Budget: $250 million

Domestic Gross: $73 million

You know your movie is a dud when its distributor can’t wait to tell the world how much money they’ve lost.

Less than two weeks after its release, Disney reported that they would take a $200 million loss on the Mars-set action epic. In doing so, the studio basically sentenced director Andrew Stanton and star Taylor Kitsch to Movie Jail.

2. Heaven’s Gate

Production Budget: $45 million

Domestic Gross: $4 million

Director Michael Cimino’s (The Deer Hunter) 1980 Western cost the equivalent of a gabillion dollars in today’s money, and forced distributor United Artists to go bankrupt. Which explains why the movie is still a sore subject, more than 30 years after its release.

3. Mars Needs Moms

Production Budget: $150 million

Domestic Gross: $6.9 million

Another costly bomb from Disney, this 2011 release forced The Mouse House to shut down the motion capture studio that made it.

Science is still trying to calculate the number of fu!@s audiences couldn’t give.

4. 1941

Production Budget: $32 million

Domestic Gross: $94.9 million

After scoring huge hits with Jaws and Close Encounters of the Third Kind, 1941 marked Steven Spielberg’s first major critical and box office disappointment.

The only good thing to come out of this 1979 WWII farce was that it forced the director to go “less is more” with his next project, Raiders of the Lost Ark.

5. Battleship

Production Budget: $209 million

Domestic Gross: $65 million

2012’s second big-budget flop headlined by Taylor Kitsch, director Peter Berg’s adaptation of the Hasbro board game proved to be a huge “miss” with audiences. In fact, that pun is arguably better than the entire film.

6. Ishtar

Production Budget: $55 million

Domestic Gross: $17 million

Like Heaven’s Gate before it, this 1987 comedy misfire is synonymous with “box office disaster.”

Starring Warren Beatty and Dustin Hoffman as American lounge singers who travel to Morocco and stumble upon a Cold War plot, Ishtar is still used today as an example of how not to make a movie.

7. The Adventures of Pluto Nash

Production Budget: $100 million

Domestic Gross: $4.2 million

2002’s mess of a sci-fi comedy marked the first of many big-budget bombs starring Eddie Murphy.

The Beverly Hills Cop star once quipped that he knows “the two or three people who saw” Pluto Nash, which is actually one or two people more than those that saw his next big movie fail…

8. Meet Dave

Production Budget: $60 million

Domestic Gross: $11 million

This Summer 2008 flop proved that Eddie Murphy failed to learn a valuable lesson from Pluto Nash: If he’s in a sci-fi comedy, audiences will stay away.

9. Gigli

Production Budget: $54 million

Domestic Gross: $6 million

When speaking of this 2003 comedy, one uses the same nervous, hushed tones as they would when talking about Voldemort.

Fun fact: The Ben Affleck and Jennifer Lopez vehicle dropped 82% in its second week, setting a record at the time.

10. Speed Racer

Production Budget: $120 million

Domestic Gross: $44 million

Based on the popular cartoon series, this long-anticipated from directors Andy and Lana Wachowski looked like a hit on paper. Then it hit theatres and, well, this 2008 release will just have to settle for slowly becoming a fan favorite.

11. Cutthroat Island

Production Budget: $98 million

Domestic Gross: $10 million

Director Renny Harlin made a pirate movie starring then-wife Geena Davis and Matthew Modine, and managed to bankrupt its studio in the process.

Everything in the above sentence makes sense. Too bad the filmmakers didn’t know then what they certainly know now.

Are you on the fence about seeing Cloud Atlas? Watch our video review below to see if you and your wallet can help save it at the box office.

It pays to have Mila Kunis and Dustin Hoffman in your corner. In a day’s work, these actors saved lives.

The Black Swan star sprung into action on Monday and she wasn’t even on screen. The actress reportedly rushed to a 50-year-old man’s side who works at her home when he started having a severe seizure, “choking, coughing up blood and vomiting,” TMZ reports. He also bit through his tongue.

A source told the website that Mila, 28, helped turn the man’s head to the side while another person at the scene stuck a wallet in his mouth to prevent choking as the actress’ friend dialed 911. Mila offered to ride with the man in the ambulance to the hospital but was assured that it “wasn’t necessary.” Thanks to Mila and her friends, the man is in full recovery.

As for Hoffman…

The Sun is reporting that the Marathon Man actor, 74, attended to jogger Sam Dempster when he collapsed in London’s Hyde Park from a heart attack. “I want to say ‘Thank you’ to Dustin Hoffman. He saved my life,” Sam said in recovery. Once the paramedics got to the scene, Dustin reportedly stayed with the jogger for 15 minutes. They were able to get Sam’s heart to start working again, with the actor praising the paramedics, saying, “Great job, guys.”

Dustin and Mila aren’t the only hero in Hollywood. From Ryan Gosling to Zoe Saldana, click the pics to see other heroic deeds.

• Apparently inspired by Miley Cyrus, Dustin Hoffman and Jason Bateman swap spit at a Lakers game. Go, team! (PopEater)
• Who should be cast in the new Teenage Mutant Ninja Turtles reboot? Besides Ron Jeremy, of course? (Wonderwall)
• Check out this video of a toddler remaking Lady GaGa‘s “Telephone” video. It’ll totally make you want to scrub yourself with a Brillo pad afterward. (Huffington Post)
• Doug Reinhardt is dating Miss World 2008. In your face, Paris Hilton! (Starpulse)
• The naked chest wars have begun. No telling how many casualties will occur before the last nipple has fallen. (Hollywood Life)

Why don’t you tell us what really happened behind the scenes of Mr. Magorium’s Wonder Emporium?

While sitting courtside for game one of the NBA Finals, Jason Bateman and Dustin Hoffman were caught on camera kissing and broadcast onto the jumbo scoreboard screen.

The two actors worked together on Mr. Magorium’s Wonder Emporium in 2007, but who knew there was passion underneath their professional facade.  Both Bateman and Hoffman are married.

Keep close for more on this story.

Celebuzz knows what those Housewives are desperate for—cutting-edge gadgets.

Several residents of Wisteria Lane turned out to Beverly Hills for the launch of the entertainment industry’s Jesus Phone: The Blackberry Bold.

Eva Longoria showed in an, um, interesting geometric number that perhaps proves she’s not preggers after all. Tony Parker‘s wife wasn’t spotted drinking any alcohol, but she could’ve merely had an early call time.

Felicity Huffman attended with thesp/husband William H. Macy, the pair chatting with screen legend Dustin Hoffman while all three died quietly inside until the moment they could jump into their hired cars and play with their new 3G toys.

The most appreciative, however, has got to be director and bedhopper Brett Ratner. While having his Bold personally engraved at an EtchStar booth, he chatted up a young blonde aspiring actress.

“I just did a pilot,” an onlooker overheard her say, while he quizzed her on other stats.

“I’ll see you upstairs,” he returned, dismissing her and grabbing his now sacred Blackberry, with three large initials burned into the back—”RAT.”

Very nice!

Fearlessly fierce funnyman Sacha Baron Cohen and Isla Fisher‘s daughter Olive turned a year old yesterday, and an illustrious assemblage of guests turned out to celebrate.

Superbad‘s Jonah Hill, Courteney Cox, David Arquette, Ben Stiller, newlyweds Ellen Degeneres and Portia de Rossi, and Jennifer Aniston convened at Cohen’s Hollywood Hills home to party down.

Also on hand: Dustin Hoffman, because every kid’s birthday party needs a clown.

Also there to attend the festivities but not pictured: Aniston’s recently rekindled flame, John Mayer. Which makes perfect sense, since he and the host have so much in common.

Several great actors of the current generation have taken the plunge and done something most would be shamed and embarrassed about—dressing as a member of the opposite sex in a movie.  

Daniel Radcliffe recently confessed that he would love to play a drag queen in a future role.

Project Runway winner Christian Siriano has also successfully exploited the term “hot tranny mess.”

In celebration of Daniel’s bold admission, take a look at the top 10 actors who’ve played cross-dresser on film. Thoughts?