15 companies that will change the world

Blinkx
CEO: Suranga Chandratillake
Disruption: Web video search and ad insertion
Disrupted: Search engines and the TV ad business

The fastest growing segment of Internet advertising is video, and Blinkx's video search engine aims to capitalize on the trend. Blinkx indexes more than 14 million hours of video available on the Web, using software that turns speech into text and counts how many times a given word pops up in a video. That allows the company to target ads to video content, putting it a step ahead of big challengers like Google and Yahoo.

Raydiance
CEO: Barry Schuler
Disruption: Lasers that cut without heating surrounding material
Disrupted: The entire laser industry -- medicine, aerospace, and beyond

Raydiance's ultrashort pulse laser is more accurate than the standard fare in the industry, and when properly tuned, it can blast away at anything from a hunk of steel to a single cancer cell. Though researchers have been using USP lasers since 1989, they've been unmanageably large and notoriously difficult to operate - but Raydiance has managed to shrink its product down to the size of a microwave.

Expensr
CEO: Reman Child and Shawn Gupta (founders)
Disruption: Simple, straightforward financial planning
Disrupted: Today, makers of personal finance software. Tomorrow, the credit industry

Combine the utility of software like Quicken with the social power of Web 2.0, and you have Expensr - a free online service that tracks your budget and spending habits, then shows you how you're doing compared to your peers. "That's the idea behind the social network," says co-founder Shawn Gupta, "to help you do better by making you aware of what other people like you are doing."

Zipcar
CEO: Scott Griffith
Disruption: Self-serve hourly car rental in urban neighborhoods
Disrupted: Car dealers and traditional rental agencies

There are no service clerks, no paper contracts, no lines. With Zipcar, you pay a $50 annual membership, then go online to see what cars are available near you. When you get to the car, swipe your wireless ID card to get in, and the keys are inside. You pay a usage fee that runs $8 to $15 per hour. Zipcar is profitable in cities where it has been operating more than two years, including Boston, New York, San Francisco and Washington, D.C., and it's ahead of competitors like Flexcar and City CarShare.

MFG.com
CEO: Mitch Free
Disruption: An online exchange for the manufacturing industry
Disrupted: Manufacturers' reps, parts brokers, and trading houses

MFG.com is rapidly becoming the eBay of manufacturing. In the past 12 months, $2 billion worth of gears, molds and machined parts were sourced and traded on the site. To participate, sellers pay an annual fee of $6,000 on average, and buyers pay nothing. Buyers describe the part they want and submit digital renderings, and industrial suppliers bid for the business. The site is on track to make $25 million in revenue, and book its first profit, this year.

Virgin Charter
CEO: Scott Duffy
Disruption: Online reservations for the budding air-taxi business
Disrupted: Commercial airlines

Air taxis - tiny, short-hop planes that are so affordable that business fliers can charter them whenever they want - are taking off. Virgin Charter, majority-owned by Richard Branson, aims to be the Expedia for this new market. By creating a portal that connects travelers to charter operators, most of whom are mom-and-pop shops, the company plans to bring more revenue into the industry, reduce the cost of operating air charter services, and waste less jet fuel.

PatientsLikeMe
CEO: Ben Heywood (President)
Disruption: An online community where patients discuss and track medical conditions
Disrupted: The health-care industry, medical research

There's plenty of basic data about diseases on the Internet, but there are few central repositories for firsthand accounts about what living with those diseases was like. PatientsLikeMe consolidates such personal accounts and helps patients track their progress. The deep and engaged community has only a few thousand members, but is already a boon to medical researchers; access to such communities of patients is a fast bypass around restrictive privacy rules.

Bloom Energy
CEO: K.R. Sridhar
Disruption: Energy generators in homes and businesses
Disrupted: Electric utilities

The company's vision is to use solid-oxide fuel cells to allow homes to generate their own electricity. The fuel cells would use (but not burn) hydrocarbon fuel, and produce just half the carbon dioxide that today's power plants do. One fuel cell should be enough to serve a home; homes could sell excess power back to the grid. Bloom Energy's biggest hurdle is cost. It needs to get the price of its machines below $10,000 apiece.

Vanu
CEO: Vanu Bose
Disruption: Software that allows mobile networks to accommodate devices with different standards
Disrupted: Wireless network providers and equipment makers

As any frustrated U.S. cell phone switcher knows, one carrier's phones often won't work on another carrier's network. That's because some use different wireless standards - the two dominant ones are GSM and CDMA. Vanu Bose, son of the audio equipment inventor, is selling equipment that could change all that. Vanu's software-defined radio uses Linux servers to help tear down the communication barriers.

Zink
CEO: Wendy Caswell
Disruption: Inkless printing
Disrupted: Desktop printers, ink cartridge resellers, and photo services

Hate dealing with empty printer cartridges? You're the customer Zink is after. The Polaroid spinoff's special paper is embedded with dye crystals, so it can create color photos without the ink. As a result, its printers can be small enough to fit in your pocket. This holiday season, Zink's partners will begin selling the printers, including one that will be embedded in a digital camera.

A123 Systems
The leading battery technology - lithium-ion - has not changed in a decade. A123 holds patents for smaller, lighter lithium-ions with significantly longer lives. A123 batteries are installed in hybrid buses worldwide and will enter consumer hybrids in 2010.

Renewable Energy Group
Biodiesel delivers around 50 percent more miles per gallon than ethanol. REG, an offshoot of an Iowa farm co-op, makes biodiesel from soybeans. It has 40 percent of the market and a distribution deal with Safeway.

Desktop Factory
The cost of rapid prototyping machines is already plummeting. Now San Francisco startup Desktop Factory is set to bring out a $5,000 3-D printer, undercutting competitors by 75 percent.

Cree
Sure, compact fluorescent lightbulbs are energy savers, but they also contain mercury. Cree is the leading maker of light-emitting diodes, which are less hazardous and even more energy-efficient. Toronto and Raleigh, N.C., are already installing Cree LEDs in streetlamps and parking garages.

One laptop per child
It isn't just Third World kids who will benefit now that Nicholas Negroponte's venture is producing its $176 laptops. The machine's innovations, such as Wi-Fi mesh networks and a power system that consumes 90 percent less electricity than standard laptops, could affect the rest of the industry.