1. Smart Parking

George Jetson's car folded into a briefcase. Robotic Parking Systems has the same efficiency in mind. The Florida company's automated garages are programmed to place cars on the floor that best suits a driver's return time. They require no ramps, and can house twice the cars in half the space. RPS has garages in Washington, D.C. (as does a rival garage company) and Hoboken, N.J.

2. Free Rebranding

It's British humor gone awry. The Design Conspiracy, a London ad firm, created a website, whatbrandareyou.com, that generates new corporate names using just a few bits of data. Intended as a joke, it has received 3 million unique visitors, and at least 20 companies have actually registered monikers such as Winnovate and Amplifico.

3. Sounding the Alarm, Then Coordinating It

As 9/11 proved, police and firefighters need to communicate during an emergency. Three members of the Chesapeake Innovation Center in Annapolis, Md.--the nation's first incubator devoted solely to homeland security start-ups--are tackling the problem. One seeks to link rescue workers' networks regardless of frequency. Another is developing tools to collect data at emergency sites. A third hopes to use mobile phones to track rescue workers in the field.

4. A Bad Smell in a Bottle

What do hookers and squirrels have in common? They are both repelled by SkunkShot. Connovation, a New Zealand company, created the foul-smelling gel to ward off garden pests. Police in Compton, Calif., have found that it keeps prostitutes and drug dealers out of abandoned buildings.

5. A New Kind of Tie

Sixteen-year-old Baruch Shemtov's unique neckwear line is selling well in New York City boutiques like Takashimaya. In addition to regular cravats, Shemtov sells a special "double tie" that resembles one tie on top of another. Our Doogie Ferragamo drew inspiration from his private school's dress code. "Rep stripes get pretty boring," he says. The 11th-grader now finds himself juggling Model U.N. and a profitable business.

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