As "American Idol" celebrates its 500th episode & Season 13 comes to a close, here's our countdown of "American Idol" alums' biggest Hot 100 hits ever - and the untold stories behind the songs.


"Walk Away" - Kelly Clarkson

Hot 100 Peak: No. 12 (2006)

"'Walk Away' is so much fun to sing," says Clarkson. "To me, it's like a Prince/Annie Lennox/Aerosmith song. It's very in-your-face. I absolutely love the Annie Lennox part in the bridge. The label didn't like this guitar part in the whole song, but I do that anytime I perform it. The guitar part is ridiculous. That's where it brings in Prince. It's a little all over the place, very feisty."


"Already Gone" - Kelly Clarkson

Hot 100 Peak: No. 13 (2009)

Clarkson wrote the song with Ryan Tedder but wasn't happy when she heard another song he had written – "Halo" by Beyoncé. Clarkson accused Tedder of using the same musical track for both songs. The OneRepublic frontman issued a statement denying that the tracks were the same: "They are two entirely different songs conceptually, melodically and lyrically and I would never try to dupe an artist such as Kelly Clarkson or Beyoncé into recording over the same musical track; the idea is both hurtful and absurd."


"Inside Your Heaven" - Carrie Underwood

Hot 100 Peak: No. 1 for one week (2005)

When songwriter Andreas Carlsson heard one of his songs was going to be recorded by the winner of season three, he thought it was "The Best of Me," written with Desmond Child and John Reid. Then he was told it was a song he had written a year and a half earlier, "Inside Your Heaven." Child produced the recording and says, "Carrie can sing a song from beginning to end without stopping. She doesn't make any mistakes and it's perfectly in tune and then she sings it again even better than before. She's stunning. She's also prepared. She goes in there and she knows the song. That's rare."


"Wait for You" - Elliott Yamin

Hot 100 Peak: No. 13 (2007)

When Danny Strick from Sony/ATV Music gave Yamin this song written by Taj Jackson and Tor Erik Hermansen and Mikkel Eriksen of the Stargate production team, the season five finalist wasn't crazy about it. "My manager urged me to give it a chance and go into the studio with Stargate. Everyone smelled a hit," says Yamin. Once he heard the finished track, Yamin agreed. One change the producers made from Jackson's demo: they lowered the key for Yamin. "I performed the song at the ASCAP Pop Music Awards," he recalls. "I invited Taj to sing it with me. We did it in my key and he adapted."


"Miss Independent" - Kelly Clarkson

Hot 100 Peak: No. 9 (2003)

Destiny's Child had this song on hold for their "Survivor" album and Christina Aguilera was also interested. "She helped start the lyric for the verse and part of the chorus," says producer and co-writer Rhett Lawrence. "The song didn't have lyrics for the chorus yet, so I wrote that with Christina. We decided to make the title 'Miss Independent.' The verse starts off as a song about a girl who's independent minded, then I decided to slip it in the opposite direction for the chorus. Then Christina decided not to record it. I played the track for Kelly without any lyrics, just the original track and she immediately said she wanted it to be her first single." Lawrence flew to Miami where Clarkson was filming the "From Justin to Kelly" movie. "We wrote the bridge and lyrics together because I wanted her to be part of it and she did a great job."


"Sorry 2004" - Ruben Studdard

Hot 100 Peak: No. 9 (2004)

Clive Davis was looking for a song that would garner radio airplay for Studdard and please "Idol" fans at the same time. Harvey Mason, Jr. and a team of writers composed this tune especially for the second season winner at a late-night writing session. "We called it 'Sorry 2004' because it was about Ruben apologizing for everything he did in the previous year and saying how he was going to spend 2004 making up for what he did," says Mason. The single was recorded over two days in Los Angeles and Mason found Studdard to be very mellow and easy-going. "He gave a great vocal performance."


"This Is the Night" - Clay Aiken

Hot 100 Peak: No. 1 for two weeks (2003)

The top four finalists from season two met with Clive Davis at his Beverly Hills Hotel bungalow and he played two songs for them without revealing which contestant would be singing which song. Aiken recalls, "He played 'This Is the Night' first and we realized this is going to be the 'A Moment Like This' of this year. I almost cried. 'This Is the Night' gave me chills. Then he played 'Flying Without Wings' and it was a great song and I loved it, but it didn't do what 'This Is the Night' did for me. And then he said, 'The first song I played, I'm going to assign…' and I had my fingers crossed, "Please God, let it be me, let it be," and he said, 'That's the song for Clay and Josh [Gracin].' Yes!" "This Is the Night" debuted at No. 1 the same week Ruben Studdard's "Flying Without Wings" debuted at No. 2, the first time in Hot 100 history that the top two songs on the chart were new entries.


"Home" - Daughtry

Hot 100 Peak: No. 8 (2007)

"I had already auditioned for 'Idol' and knew I was leaving for Hollywood," says Chris Daughtry, who had been writing songs since he was 16. "I was sitting on my couch – oddly, I wrote 'Home' at home. I felt it was a song that could go on pop radio." A year later, when his group Daughtry recorded the song for their debut album, it had the same structure and chords that Chris had fashioned at home in North Carolina. When the producers of "Idol" asked to use "Home" for the season six exit song for eliminated contestants, Chris' reply was an enthusiastic, "Absolutely, please use it."


"Tattoo" - Jordin Sparks

Hot 100 Peak: No. 8 (2007)

Tor Erik Hermansen and Mikkel Eriksen, better known as the Stargate production team, met with Amanda Ghost and Ian Dench at Battery Studios in New York to write "Tattoo," a title suggested by Ghost. "Amanda comes from a more artistic side. She does her best writing when she’s having fun," says Hermansen, adding, "Jordin was a pleasure to work with. She was wide-eyed and happy to be there. That’s one of the fun things about 'Idol.’ The singers are getting a chance of a lifetime and they’re really into it."


"A Moment Like This" - Kelly Clarkson

Hot 100 Peak: No. 1 for two weeks (2002)

"'A Moment Like This' is one of the most difficult songs I've ever had to sing," says Justin Guarini, who performed the song on the season one finale, as did Clarkson. "No conspiracy theory, it was written before anyone knew I going to be part of the finale. It's just not written for someone who does what I do. I struggled and struggled with it in the studio….There was a point after the finale when I was with Kelly and I said, 'Baby, I did everything, but you're going to win tomorrow night. I love you.'" "A Moment Like This" was the first "Idol" song to go to No. 1 on the Hot 100. When it jumped 52-1 the week of Oct. 5, 2002, it broke the Beatles' 38-year-old record for the biggest leap to the top ("Can't Buy Me Love" rocketed 27-1 the week of April 4, 1964).