They're back: Led Zeppelin, who almost wasn't

There's a lot of math and science in music. Even with Led Zeppelin. The only band to have every one of its albums hit the US Billboard Top Ten, Led Zeppelin has sold over 300 million albums. Last night they played London's The O2, in a performance like oxygen to their fans.

Remember that echo on Zeppelin I and II that came before, and not after, the music? Zep guitarist Jimmy Page says he invented the technique, contradicting others who say the echo is the result of someone accidentally leaving the recording tapes in a hot car.

So who came up with the name Led Zeppelin? You can thank Keith Moon, then drummer for the Who, who said Page's erstwhile name for his group, The New Yardbirds, would go over, not like a lead balloon, but like a lead Zeppelin. Page removed the "a" from "lead" and the rest is history.

Although it almost wasn't. In high school, Jimmy Page was interested in science and almost took a job as a Lab Assistant. Now that would have been a rocking lab.