It's easy to forget how one song used as a TV theme can change a group or a composer's life. That's what happened to Ed Robertson of The Bare Naked Ladies, after he penned the title tune to The Big Bang Theory, which ran for 12 seasons and is still on in reruns. 

Robertson gets rewarded every time that song plays at the top of an episode and he admits that, even though his band made money from its previous albums, nothing quite compares to the amount he rakes in for that one tune - which is more than all the Ladies' other work combined. 

"Robertson is reluctant to divulge the exact amount he’s made on royalties between the show’s original run and syndication, but the amount appears astronomical. “It’s not seven digits, and it’s not 10 digits, but it’s in between those somewhere,” he says. “I don’t want to be gauche and specific about it either, but it’s been life-changing.

“The Big Bang Theory absolutely changed everything for me,” Robertson adds. “It’s been like having a number one hit multiple times a year, every year for the past decade. It’s the gift that keeps on giving.”

And he's not the only one. How'd you like to make $700,000 a year for something you did back in the mid-90s? That's what the co-composer of the "Friends" theme rakes in from a show that hasn't been in production since 2004. 

Inside The World Of TV Theme Songs