If an unkempt man pitching what looked like a souped-up typewriter walked into your office, would you have the wisdom to invest in his company?
Mike Markkula did. He was an early investor in Apple and eventually one of its CEOs. Just as inspiration: If you'd taken a one-third stake in Apple back then and held on to it, that stake would be worth $190 billion today, based on the company's current market capitalization.
Of course, there's only ever going to be one Apple—but in the past few years, a growing number of technology platforms and new companies have begun offering smaller investors a chance to be part of this generation's most innovative and disruptive companies. These are upstarts that are building billion-dollar enterprises at warp speed. A poster child is virtual reality company Oculus Rift, which was bought for $2 billion by Facebook in March, just two years after it was founded.
New federal regulations are also likely to open the door wider to smaller investors to become start-up, angel or microventure investors. In short, the opportunities that used to be reserved for the wealthy and well connected are coming your way.
"Historically, participating in private investment has been limited. Minimum investments are typically $1 million, and it takes months to network in the field. We are expanding participation," said Ryan Caldbeck, CEO of San Francisco-based CircleUp.
CircleUp is one example of the new entrants in the private equity space. It's a two-year-old tech company that gives accredited investors, those with $200,000 in income or $1 million in assets, excluding their homes, the chance to invest in consumer-brand companies start-ups online.
Just because there are more chances for you to invest, of course, doesn't mean you'll make a ton of money—or even any money—doing it. Very few professional angel investors or venture capitalists make money. Data on angel investing is scant, but a study by the Kauffman Foundation found that only about one-fifth of venture capital funds beat a public-market equivalent by enough to make their fees worthwhile.
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Why is it so hard to pick winners? You have to be able to recognize an innovative idea, evaluate its chances of success, and then have a hefty dose of luck that something like an act of God or major scandal doesn't mess up the company's fortunes.
And how do you know a good bet when you see it? According to Clay Christensen, Harvard Business School professor and one of the world's top thinkers on disruptive innovation: "In order for a start-up company to succeed, almost always they need to either create a huge new market where there wasn't one before, or find a new way to be more profitable serving the least attractive customers of existing markets. If a start-up's ambition is to beat well-established incumbents by building a better mousetrap, their odds of success are extremely low," he said.
Here are five ideas for ways you could get involved in disruptive companies—either for money or pleasure.
Use a crowdfunding approach. Many great companies got their starts on crowdfunding platforms. San Francisco-based water filter maker Soma, for instance, raised its money on Kickstarter (CNBC's No. 49 Disruptor). At the moment, crowdfunding sites don't allow equity investing, but that may change if the SEC loosens its regulations on accredited investors, as it is expected to later this year.
Indiegogo, another crowdfunding site, has already said it is exploring options to offer equity investing to small-scale investors depending on what the SEC says. Even before that, though, you can be involved in high-profile innovators like Oculus Rift, the Irvine, California-based virtual reality company that raised $2.4 million of seed funding on Kickstarter.
A high-volume crowdfunding site gives you the chance to take a portfolio approach to start-up investing, which most experts suggest. That means that you set aside $10,000, $50,000 or whatever you can afford and invest it in a number of different companies.
If you have enough money, become an angel. CircleUp, for instance, allows anyone who is an accredited investor to easily become an angel in consumer brand companies. Typical investments are in the five figures, Caldbeck said, but companies decide what kinds of minimums they want to set for their investments—they can be as high as $50,000 or $100,000. No investors have made money on CircleUp, which is only two years old, but the brand companies on the platform are growing their revenue at an average of 80 percent a year, and several have received investments from venture capital firms.
AngelList (CNBC's No. 26 Disruptor) is another online platform bringing transparency to this previously opaque world; it lists companies raising money, as well as prominent investors who might be accepting limited partners in their venture capital funds. If you prefer to work offline and join one of the proliferating angel investment groups, the Angel Resource Institute is a good place to start.
Look for opportunities globally. In the United States, there is money in search of opportunity. Internationally, there is opportunity in search of money, so your chances of being able to invest in a top innovator are higher. "Look for the great filters in the region, women and men, and get to know the ecosystem if you have a taste for the risk and the stamina for it," said Christopher Schroeder, a venture investor and the author of "Startup Rising," a book about start-ups in the Middle East.
Dave McClure, who runs the famous Silicon Valley start-up incubator 500 Startups and is also a start-up investor, said that 25 percent of the companies he invests in are now international. He expects that to grow to 50 percent within the next five years.
McClure gave an example of a company he invested in called Viki, which provided video subtitles in foreign languages and which was acquired after four years by Japanese e-commerce giant Rakuten for $200 million.
If you're interested in international investing, you can take two approaches: Network among the angel groups to find venture capital funds working internationally. Or, if you have connection or interest in a particular market, you can do your own on-the-ground reconnaissance and networking.
"They're really quite accessible and not nearly as foreign as you tend to think," said McClure. "They're less than a 24-hour flight. There are modern-day Marco Polos happening in greater and greater numbers."
It's likely that crowdfunders and new technology platforms will broaden their scope to allow international equity investing at some point, too.
Work through the public markets. Not every innovator is a small, privately held start-up. If you have some money that you want to have fun with and you want to invest in entrepreneurial energy, you can take the old-fashioned approach to all this, buy the stock of a company you admire, and hold on to it. In June of 1984, 30 years ago, Apple was trading at about $25 a share. The stock peaked at $700 last year and has since split. Buying shares of Apple when it was a small publicly held company wouldn't have made you a billionaire, but it would have created quite a nest egg.
Remember to be skeptical. Companies that innovate and succeed like Apple come along only a few times in a generation. You should invest only as much as you can afford to lose. Recognize that start-up investing is a particularly high-risk, high-reward game, so it's important to limit your exposure.
But there are many disruptive start-ups making history in small and large ways. As the story of Oculus Rift shows, technology is accelerating the pace of success. And there are lots of new chances for you to be part of those success stories.
—By Elizabeth McBride, special to CNBC.com