Donald Trump has announced the official line-up for Celebrity Apprentice in 2012, his biggest cast yet. If you're a reality-TV junkie, a lot of the contestants are familiar faces. But for a lot of people, skimming down the large list has them asking who? Here's the run-down of who's taking on the Trump challenge and why they're famous.

Clay Aiken was a runner-up in the second season of American Idol in 2003. Although he was signed on to RCA Records shortly afterwards and starred in Monty Python's Spamalot in 2008, he might be more famous for clashing with Simon Cowell. Being in front of Trump is more intimidating than (being in front of Cowell), the singer told TODAY.com. That's because you realize his success is real outside TV. Whereas with Cowell, I don't deny him his value - but singing is not his expertise.

Michael Andretti is an IndyCar race car driver and team owner who, according to the Indianopolis Motor Speedway, is one of the greatest Indy car drivers of all time. However, he and his race car legend father, Mario Andretti, are both known for being unlucky on the Indianapolis 500, whether it be failed fuel pumps or brake fires. The family's bad luck has been dubbed The Andretti Curse.

Teresa Giudice is star of Bravo's The Real Housewives of New Jersey. She made tabloid headlines when she and her husband, Joe, faced foreclosure of their mansion and filed for bankruptcy. Known for her lavish lifestyle on the show, Giudice told InTouch weekly the ordeal was humiliating and blamed it on tenants failing to pay rent and a business lawsuit involving her husband. Her financial experience is sure to be tested on Celebrity Apprentice.

Victoria Gotti is daughter of convicted New York mobster John Gotti. Instead of getting into the mafia trade, she used her name to achieve success with a short-lived reality show, Growing Up Gotti on A&E from 2004-2005 and as a New York Post columnist. Her father was sentenced to life for racketeering and five counts of murder in 1992, when she was 30 years old.

Lisa Limpanelli made a name for herself in stand-up comedy with her raunchy and offensive jokes. She's often invited to celebrity roasts, and once said of Donald Trump in a March 2010 Comedy Central special: Donald, tonight people will make fun of your looks. F--- 'em. You've always gotten beautiful women. You've ruined more models' lives than bulimia. You've disappointed more women than 'Sex and the City 2.' On Thursday, TMZ caught her lashing out at NBC for placing her in the back row for a Knicks game while placing contestants Teresa Giudice and Dayana Mendoza in the front.

Dayana Mendoza is former Miss Universe 2008 and former Miss Venezuela 2007. She has modeled for Max Mara and Versace but is probably more well known for nude photos from a jewelry ad that surfaced a year after she won the Trump-owned competition. Instead of denouncing the pics, like the competition had for beauty queens Carrie Prejean, Katie Rees and others, the Miss Universe Organization released the photos because they were artistic, rather than salacious. They're just beautiful, president Paula Shugard said, according to the Today show.

Dee Snider was the frontman for heavy metal band Twisted Sister in the 1980s. He went on to create several other bands and became a radio host, but he's most famous for his screaming vocals and out-of-control long blonde hair.

Paul Teutul manufactures custom motor cycles and has a very appropriate blonde handlebar mustache, but gained fame from starring in the reality television show American Chopper with his son, Paul Teutul, Jr. The show about their company, Orange County Choppers, gained ratings when Teutul Sr. fired his son, The New York Times reported.

Arsenio Hall is a comedian and actor best known for The Arsenio Hall Show which aired from 1989 to 1994. Then-presidential candidate Bill Clinton was a guest on the show in 1992 and played the saxophone. A drop in ratings eventually led to the show's cancellation and he hasn't reached the level of celebrity he had during his show since then.

Adam Carolla hosts The Adam Corolla Show, which was named the Most Downloaded Podcast by the Guinness Book of World Records.

Lou Ferrigno is a bodybuilder who starred as the Incredible Hulk in the CBS series of the same name. He also made fun of himself in the 2009 comedy, I Love You Man.

Penn Jillette is a magician who also was a contestant in Dancing With the Stars in 2008 (he was the first contestant eliminated).  In 1999, he was granted a patent for the Jill-Jet a hot-tub jet meant for women's pleasure.

George Takei played Hikaru Sulu in Star Trek in the 60s. He is also a proponent of gay rights and is active in local and state politics. In 2008, he lived in the Australian bush for 21 days in the UK version of I'm a Celebrity... Get me Out of Here!

Cheryl Tiegs was a famous supermodel in the 1970s. She was the cover model for the Sports Illustrated Swimsuit issue three times.

Debbie Gibson had four singles in the Top 5 of the Billboard Top 100 in 1987: Only in My Dreams, Shake Your Love, Out of the Blue, and Foolish Beat.

Tia Carrere is a Grammy award-winning singer and played Cassandra Wong in Wayne's World and Wayne's World 2. In addition to various acting gigs and her music career, she was the cover model of Playboy's January 2003 issue.

Aubrey O'Day is a singer that was on Making the Band 3 in a former member of the girl group Danity Kane. She also modeled for Blender, Playboy and other magazines.

Patricia Velasquez is a Venezuelan supermodel who has modeled for Dolce & Gabana, Victoria's Secret, and other big designers. She played Anck-Su-Namun in The Mummy and The Mummy Returns