You could argue the biggest legacy of Ford or Toyota isn't a car or truck, but rather the management and measurement systems their manufacturing processes enabled. The same is true for America's first railroad companies, which in many ways pioneered the real-time accounting and data practices now commonplace. 

The Wright brothers towering legacy will always be the flying machine they invented. But today's startups routinely apply one of their early test methods. As Innosight's Scott D. Anthony, no stranger to product launches, tweeted not long ago, the Wrights "figured out [the] importance of [a] 'minimum viable product' when they built a wind tunnel to test ideas." 

In his recently released bio of the Wright brothers, David McCullough describes the wind tunnel as "a wooden box 6 feet long and 16 inches square, with one end open and a fan mounted at the other end....the box stood on four legs about waist high."

From 1893, the Wrights had owned and operated a bicycle shop in Dayton, Ohio. To build their wind tunnel, in 1901, they relied on available materials in the shop. They used spare steel to build model wings of different shapes, sizes, and thicknesses. They tested the wings at different angles and simulated-wind velocities. And they recorded all the data. 

You might think this homespun manner of testing is nothing profound. But at the turn of the 20th century, inventors often jumped right into building pricey prototypes. The Wright brothers turned this build-it-first thinking on its head by devising cheap, easy-to-construct product tests. Two years before the wind tunnel, they were testing air-flow assumptions with handmade kites. "Not only could they build kites more rapidly, but they hadn't risked life and limb or depleted their bank accounts when it turned out that they got something wrong," writes Anthony in Fast Company. 

Today, you can find the Wright brothers' tunnel-testing principles everywhere. For example, manufacturers of all stripes test their innovations by first producing samples. Michael Lewis, founder and CEO of Forever Collectibles, sold $10 million in ugly Christmas sweaters last winter. He initially feared the sweaters were a risky foray into apparel for his firm, which makes tchotchkes and baubles. Then the samples arrived. "Now I know," he told Inc. "I can just tell, from my instincts and reactions, that we have a winner." When his customers saw the ugly-sweater samples, they agreed.

Likewise, JadeYoga, a renowned maker of yoga mats, didn't enter the mat business by accident. Its parent, Jade Industries, had been making non-slip, natural-rubber rug pads since the 70s. "We had a couple customers who we knew were using rug pads as [yoga] mats," explained company president Dean Jerrehian. By 2001, his lists of wholesale rug pad customers included more and more yoga businesses. So Jerrehian test-marketed an eco-friendly, slip-free mat. "We found a list of yoga studios and sent out 500 five-by-eight hand-sized samples," he said. The company got 300 phone calls back, a staggering response. "That was how we knew," he said.

Of course, many startups are not manufacturers. Even then, you can still find cheap, small, and fast ways to test product ideas. In March, 2008, the founders of Dropbox garnered 75,000 signups from an online video on Digg demonstrating the product--even though the product wasn't ready yet. The online video was a speedy, low-cost, low-risk way to test a minimum viable product. "A failure of this test [didn't] necessarily mean that Dropbox wouldn't work--it could mean that the quality threshold was higher than expected, or that Digg users weren't ideal early adopters," notes N. Taylor Thompson in the Harvard Business Review. 

Given the well-chronicled success of companies like Dropbox and the way lean startup techniques have taken hold of the culture, you might think any founder worth her slide deck would orient her idea around testing a minimum viable product. But it's just not true. Tina Weber, who runs Boston's lean startup challenge, says most entrants make the mistake of trying to compete based on ideas alone--rather than by demonstrating customer demand through a small-scale test. A test, she adds, could be as simple as building a landing page: a one-page web site with a "buy" button. This basic online form will allow you to quantify prospective customer interest (based on how many people push the "buy" button). You'll also be able to collect contact information from those prospects, surveying them on price points. That feedback can help you raise money--money you'll need when it's time to actually build your first real prototype.

The overall concept is to test your ideas by making small bets on them. Jessica Herrin, founder of jewelry seller Stella & Dot, enlists the company's stylists "in the trial-and-error process of selecting products," writes Amy Wilkinson in The Creator's Code: The Six Essential Skills of Extraordinary Entrepreneurs. At meetings, Herrin hands out Post-Its in two different colors--one for "love it," one for "lose it"--so her staff can provide fast, effective feedback on products under consideration. "I try to have this framework for decisions, which is, 'How do I fire bullets before cannonballs so when I recalibrate my target, I still have gunpowder enough to do the big thing?'" Herron tells Wilkinson.

It's fitting that heavy equipment is in her metaphor, given the role played by small bets in the advent of flying machines.