When are Led Zeppelin not Led Zeppelin? When a descendant of the inventor whose aircraft gave the band its name threatens to file a lawsuit if the group plays a concert in her home country.

It all went down on Feb. 28, 1970, when the band's scheduled Copenhagen show hit a snag courtesy of Eva Von Zeppelin, who'd first clashed with them the year before, when Led Zeppelin visited a Danish television show to tape a performance. Already unhappy that someone else was making money off her family name, Von Zeppelin criticized the group for sounding like "shrieking monkeys."

Things got even worse backstage, when a pleasant conversation over tea led to an uncomfortable gaffe. "We invited her backstage to meet us, to see how we were nice young lads," Jimmy Page later recalled. "We calmed her down but on leaving the studio, she saw our LP cover of an airship in flames and she exploded! I had to run and hide. She just blew her top."

Faced with a Copenhagen date on the calendar and the threat of a lawsuit from Ms. Von Zeppelin, the band improvised. "Then we shall call ourselves the Nobs when we go to Copenhagen," shrugged Page. "The whole thing is absurd." And thus did Led Zeppelin become the Nobs for one night.

As author Roy Carr later noted, this wouldn't be the only time the band had fun with its name; they later printed up 'Red Zepperin' t-shirts making light of an emcee's pronunciation during a Japanese tour. And as far as drummer John Bonham was concerned, they could have kept right on being the Nobs.

"Personally speaking," Bonham cackled to Carr, "we should have continued as the Nobs. Just think what our album covers could have looked like!"

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