The public just can't seem to get enough American Idol.

Just when you think folks might have had their fill, and the show might be heading for a downturn, it posts its biggest numbers ever.

"Right before the fifth season started in January, the producers and Fox executives believed American Idol was due for a cooling period. "They and most critics just couldn't believe it could continue its phenomenal climb in ratings," says Susan Young, a MediaNews TV critic. "When the premiere clocked more than 35 million viewers, it rocked even the true believers."

Over the years, the American Idol phenomenon has moved beyond the small screen to the Billboard record charts and the concert stage.

Most notably, Kelly Clarkson, the first-ever champion (right), is now one of the biggest-selling recording artists around and a formidable draw at major performing venues. She attracted huge crowds across the nation during her "Addicted" tour this summer.

Other idols, including Fantasia Barrino (the Season 3 winner) and Carrie Underwood (the Season 4 champ), also have jumped to the big leagues both musically and in Fantasia's case, a hit TV biographical movie.

While Season 6 is right around the corner, those who want to relive Season 5 may find the American Idols Live tour just what the doctor ordered -- it rolls into the Bay Area tonight after hitting Sacramento last night. Catch Taylor Hicks and company live before the tour ends!

Matt Richenthal is the Editor in Chief of TV Fanatic. Follow him on Twitter and on Google+.