Jealousy is probably the least attractive emotion in entrepreneurship. Ideally, we'd all like to be the kinds of people who put others first, who care about improving the world more than making money, and who recognize there are enough good ideas and opportunities for success to go around.

Then again, we're only human.

We all have those moments when we see a business that's so simple or so lucrative -- or both -- that we kick ourselves for not having thought of it first. I prefer to channel those moments into something positive, however, realizing that if "those people" could do it, so can any of us. For inspiration, here are five nearly insane (and often insanely lucrative) businesses that actually worked.

1. The Pet Rock.

Earlier this year, the world lost someone I think of as perhaps the greatest entrepreneur of all time: Gary Dahl, freelance copywriter, bar hound, and inventor and marketer of the Pet Rock. Back in 1975, while knocking back a few cold ones in a California bar, Dahl told friends he had a new pet who never needed to be fed, walked, or trained: a pet rock.

The joke turned into a business, and for about five months from 1975 to 1976, Dahl sold 1.5 million Pet Rocks, at $3.99 each. (The key was the witty owner’s manual he included with every rock.) He became a millionaire almost overnight.

2. The "Million Dollar Home Page."

This has to be one of the strangest yet most successful odd businesses of all time. A decade ago, a graduate student named Alex Tew in England convinced people to buy pixels on a webpage for $1 each. The idea took off, and he ultimately made more than $1 million from the stunt.

There have been a lot of copycats since then, Tew said in an interview, but added, "The idea only works once."

3. Professional line standers.

There's so much great stuff to do in New York City. The only problem is you have to wait in line for so much of it. Enter the world of professional line standers, starting with Same Ole Line Dudes, which got its start after its founder, Robert Samuel, was hired (and made $325) to stand in line for an iPhone 5 a couple of years ago. Now he and his fellow line standers charge $25 per hour.

"I'm very grassroots," Samuel told Business Insider. "When there's a line that goes around the block, I go and work the line… 'Are you hot, tired? Don't want to do this again? I'll do it for you.'"

4. Free conference calls.

I have to admit, I use this one all the time but I had no idea until recently how it works. How can a company exist that allows users to host conference calls for free? It's actually quite brilliant: under a 1996 law, small rural telephone companies are allowed to charge larger phone companies a per-minute fee when those larger companies' customers call into the smaller ones' areas.

The eponymous FreeConferenceCall.com simply uses phone numbers in those area codes for its service, and takes a small commission on each call. As of 2011, they were doing $23 million in revenue.

5. The "I Don’t Care" phone company.

Finally on this list, another phone idea. Back in the 1990s, before everyone had cell phones and unlimited long distance, callers often had to choose a long distance company on operator-assisted calls. About 3 percent of callers didn’t see much difference between carriers, and would tell the operator "I don’t care" or "It doesn’t matter" when asked which long distance service they preferred.

Enter a Texas entrepreneur named Dennis Dees, who started a long distance reseller literally called "I Don’t Care," and which reportedly socked users with expensive per-minute charges. (His company also did business under names like "It Doesn’t Matter" and "Whatever.")

Published on: Aug 14, 2015
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