It's a warning made to many young, aspiring rock stars: don't quit your day job.

But launching a career in show business doesn't usually happen overnight and it rarely happens for free. The money required for those beginning stages has to come from somewhere, right? And for those who are really serious about making the big time, chances are some less-than-thrilling, poor-paying and maybe even disgusting jobs will have to be taken.

In a lot of cases, these jobs end up being the very reason an artist can afford to buy a few days of studio time, or make enough copies of their demos to disperse to potential fans, or even simply fill up the tank to make it to the record label's office. For instance, Kurt Cobain found work as a janitor in order to finance the making of Nirvana's first demo recording.

In rarer circumstances, music wasn't even the original idea and other plans for entirely different careers were made. Gene Simmons, for example, got his bachelor’s degree in education and taught sixth grade students in New York City for a time.

Below, we're running through some of the most fascinating jobs held by 40 rock artists before they became famous for music. For the purposes of this list, we've chosen to exclude food service jobs, mainly because it's incredibly common. The jobs you'll read about here are unique, eclectic and will likely surprise you.

Rock's 40 Most Fascinating Pre-Fame Jobs

For these artists, quitting their day job worked out in their favor.

Gallery Credit: Allison Rapp

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