The rise of large corporations dominates much of the narrative of 20th-century business. Yet many of the innovations that have advanced industry, enlightened society, and deepened culture sprang from small companies. If you don't already appreciate the impact that entrepreneurial businesses have on your every waking hour, just try to imagine life without the following.

Hard hat
Edward Bullard, Inventor

The Great War didn't make the world safe for democracy, but it did make it a little safer for construction workers. The "hard-boiled hat" was inspired by the helmets doughboys wore, according to protective-equipment company Bullard, which patented the product in 1919. Originally made of steamed canvas and glue, hard hats also appeared in aluminum and fiberglass before plastic prevailed. No significant variations emerged until 1996, when Bret Atkins created the Western Outlaw, a cowboy-hat version with the advantage of serving as two Village People costumes in one.

Foot Sizer
Charles Brannock, Inventor

Proust can keep his madeleines -- our favorite sense memory is the cool-metal caress of the Brannock Device. The son of a shoe-store owner, Charles Brannock spent his college years designing an instrument to replace the rulerlike stick that shoe salesmen used to measure feet. The result: a black-painted aluminum plate with sliding gauges for heel-to-toe, width, and arch measurements. Virtually unchanged in 73 years, Brannock's invention is still produced by the Brannock Device Co., in Liverpool, N.Y., which has sold more than a million of the devices since production began in 1929.

Parking Meter
Carl Magee, Inventor

He may or may not have been a smokin' preacher, but the Rev. C.H. North won his footnote to history with an unrelated claim: he was the first person in the United States to receive a parking ticket owing to an expired meter. That was in August 1935; a month earlier the Dual Parking Meter Co. had installed its breakthrough Park-O-Meters around Oklahoma City, which paid $23 a pop for the devices. Dual Parking (now POM) was founded by newspaper editor and entrepreneur Carl Magee shortly after he was named to Oklahoma City's Chamber of Commerce Traffic Committee. As for North, the good reverend argued in court that he had stopped just for a minute to run into a store and get change. The judge dismissed his case.

Phillips-head screw
Henry Phillips, Inventor

"It's not a bug; it's a feature." That first-line defense of programmers everywhere also applies to the low-tech Phillips-head screw. Do-it-yourselfers hate the distinctive fastener for its tendency to "cam-out," or slip, when plied with a screwdriver. But it was that intentional design flaw that made the Phillips almost impossible for assembly-line workers to overscrew, a feature that endeared it to automakers, who were its first adopters. Although the product, patented in 1936, quickly became the standard for a variety of industrial and consumer uses, its inventor, Henry Phillips, never manufactured a single screw. Instead, he set up the Phillips Screw Co. to license his recessed-cross screw design.

Shopping cart
Sylvan Goldman, Inventor

Imagine grocery shopping as rush hour on a single-lane road. That's what it would have been like if two Houston supermarket owners had popularized their vision of outfitting grocery stores with a track that customers would push their baskets along while plucking items from the shelves. Fortunately, Sylvan Goldman had a better idea: cross two wire baskets with a folding chair and put the whole contraption on wheels. In 1937, Goldman, whose family owned supermarkets in Oklahoma City, began advertising his invention as a new "No Basket Carrying Plan." The carts became a hit and turned Goldman into a multimillionaire.

Aerosol-can valve
Robert Abplanalp, Inventor

Not with a bang but with a whimper. That's how the early aerosol cans tended to fizzle out. As they sat on the shelf, they would leak and depressurize, eventually releasing only a sad little hiss. Then, in 1949, Robert Abplanalp, a 27-year-old machine-shop operator from the Bronx, gladdened the hearts of whipped-cream lovers everywhere by inventing a cheap, reliable aerosol-can valve that could be mass-produced. Today his company, Precision Valve Corp. -- which is based in Yonkers, N.Y. -- claims that people use its products a billion times a day. As for Abplanalp, he collected close to 300 aerosol-related patents and was named to Richard Nixon's "kitchen cabinet."