
Is this the newest " triple threat?" Charlie Sheen, who is now apparently in the music business, sat down with Snoop Dogg and Rob Patterson, the musical director of his tour, My Violent Torpedo of Truth/Defeat Is Not an Option, which kicked off this weekend in Detroit. (Note: He is of no relation to Robert Pattinson of Twlight fame.) Sheen tweeted, "Warlock meets his makers-music makers that is @SnoopDogg @robpatterson666 get ready to rock the Sheenius within!"

One down, 11 to go on Dancing with the Stars this season. Remaining competitor Kirstie Alley and her dance partner Maksim Chmerkovskiy gave each other a bit of encouragement for the weeks ahead. Alley retweeted Maksim's photo and message: "Love it when @kirstiealley and I are like that...which is always...except when she gets violent! Kidding :)"

This past week has been quite the roller coaster for Britney Spears. She hit the stage in Las Vegas, taped a performance in San Francisco for Good Morning America, her album, Femme Fatale, was released, and she did a Jackass stunt on Jimmy Kimmel. While in Sin City, her father and conservator, Jamie Spears, met up with some drag performers, prompting Britney to tweet, “Even my dad had a great time!”

Last week, it was Kirstie Alley and George Lopez going back and forth on Twitter in fierce 140-character rounds. But this week, the heated tweeting involved Saturday Night Live alumni Norm MacDonald and Steve Martin. The conflict began when Martin posted this picture and accompanying tweet: "I can't find my hat. I've looked everywhere. If you've seen this hat please let me know." Allegedly having not seen the photo, MacDonald tweeted, "@SteveMartinToGo. I had no hat and felt sorry for myself. And then I met a man with no head." The "feud" worked its way out when MacDonald appeared on Late Night With David Letterman to explain his confusion. Martin sarcastically followed up with this tweet: "Just saw Norm MacDonald on Letterman. Accused of misreading Norm MacDonald's tweets. Can't respond, due to length of Norm MacDonald's name."

Mariah Carey just rang in her 42nd birthday and to celebrate, the butterfly lover—and eternal 12-year-old girl—hand painted a pink and blue butterfly on her baby bump. In case it wasn't clear, the singer wrote "dem babies" above the symbol and tweeted, "My attempt @ festiveness… Comin soon #dembabies!"

As one of the first male celebrities to admit to using a flat iron, Ryan Seacrest has long been known for maintaining a well-coifed image. In this photo, a security guard with an umbrella escorts the American Idol host to set. He tweeted, "Raining on the walk over to the studio... gotta make sure the hair doesn't frizz ;-)"

The creativity flowed on the set of Glee, where actress Lea Michele photographed her co-star Cory Monteith and another Gleek grabbing a late night snack—the two warmed some pizza by a portable outdoor heater.

MTV reality stars are like birds of a feather. At a Cosmopolitan event, Jersey Shore's DJ Pauly D and Run D.M.C.'s frontman and Run's House star Rev Run offered a double dose of peace. Run tweeted, "Me & @PaulyD chillin 2nite."

Desperate Housewives star Eva Longoria gave a shout out to celebrate her co-star and close friend Marcia Cross on her birthday. The actress tweeted, "Happy Birthday to @reallymarcia, my sister Marcia Cross!!! I love U!"

Glee's resident bad boy, Mark Salling, showed his softer side in this picture with his grandmother. Salling, who's originally from Dallas, Texas, tweeted, "The best part of coming home is my 92 year old grandma Bess, a living treasure."

The iconic Cher could potentially be confused for the U.K.'s X Factor star Cher Lloyd, who also dons bright red hair these days. The Burlesque star tweeted a photo to her fans (a.k.a. "lovelies") before heading off sleep.

The same week Courteney Cox was photographed on an island holiday with her Cougar Town co-star Josh Hopkins, her estranged husband David Arquette was enjoying an exploratory trip to Chile. The upcoming star of Scream 4 was recognized for his role in the masked slasher franchise. Arquette tweeted, "Look at the Chocolate treat that greeted my at my Hotel! Haha - Ghostface Lives!"

Last weekend, Perez Hilton celebrated his 33rd birthday by throwing a " Blue Ball" in Hollywood. Earlier in the week on his actual birthday, Hilton recalled earlier days with good friends, including Amanda Bynes, Katy Perry, Michelle Trachtenberg, and Emmy Rossum. Hilton retweeted this "epic photo!!!" from Bynes.