RIHANNA TOPLESS VACATION PHOTOS: RIHANNA is the latest celeb to have racy photos of her hit the 'net. But don't expect her to complain or get the FBI involved because SHE'S THE ONE WHO POSTED THEM!!!

The one above and the one below are among a ton of sexy pics RiRi posted on her Facebook page of her Hawaiian vacation. You can peep the rest HERE.

SIMON COWELL ROBBED AFTER ONE-NIGHT STAND: SIMON COWELL'S horniness almost cost him some major trade secrets after he became the victim of a one-night stand who wanted more than his tight black t-shirt clad body. TMZ reports that in the new unauthorized Simon biography, "Sweet Revenge: The Intimate Life of Simon Cowell" the author reveals that last October, Simon hooked up with a girl he met at a Hollywood nightclub -- and made the major mistake of taking her back to his place.

When he awoke the next morning, he discovered that she made off with a wallet full of cash and a computer containing X Factor secrets. Fortunately, security cameras caught the woman in the act, and cops were able to track her down. She handed over the computer and the wallet -- without the cash, of course.

Meanwhile ... SHARON OSBOURNE isn’t too happy about another story that involves her that's also in the book, and put Cowell on blast hard on yesterday's CBS talk-fest "The Talk". The unauthorized biography, which hits stores May 1st, suggests Osbourne left her gig on Britain’s 'X Factor' because she was upset over Simon and singer/co-judge DANNII MINOGUE'S romance. But Sharon insists that wasn’t the reason.

“I didn’t leave the show because Simon and Dannii were f******," she says. "I left because she became unbearable. She started bossing everyone around, even the producers. [She] wanted to be the mistress of Simon - and the mistress of X Factor.” Sharon also claims Simon was involved with two women while he was romancing fiancée Mezhgan Hussainy. She adds that the book is “none of my business,” but brought it up because she’s upset at being “dragged into his little world of debauchery.”

'DANCING UPDATE' - ELIMINATION NIGHT: GAVIN DeGRAW was eliminated on last night's "Dancing With the Stars". Former "Family Matters" star JALEEL WHITE joined Gavin in the Bottom Two, and then beat him in a cha-cha dance-off before the judges.  To watch video of the "Dance Duel" hit up the link below.

On a related note ... MARIA MENOUNOS had a bit of a wardrobe malfunction last night. Her fringed top showed off a little more under-boob than she probably intended when she waved to the crowd. I'm not complaining, I'm just sayin' ...


BABY POOP: "True Blood" true-life couple ANNA PAQUIN and STEPHEN MOYER are expecting their first child together this fall. Stephen has two children from a previous relationship. The couple wed in 2010.

2. "Life & Style" magazine "exclusively" reveals that "Sabrina the Teenage Witch" MELISSA JOAN HART has been fetused with her third child! "You can barely tell," says their source, "but there's a teeny-tiny little bump."

CELEBRITY ENGAGEMENT RINGS PHOTO GALLERY: With all the chaos surrounding the engagement of BRAD PITT and ANGELINA JOLIE, the website PopSugar put together a photo gallery of 100 celebrity engagement rings. You can check out as many as your free time allows HERE.