No. 26: Hayden Hamilton

Age: 30*

Location: Portland, Ore.

2006 revenue: $50,000

Employees: five

Year founded: 2005

After seeing the overflow of abandoned printouts while working at Ford Motor (F, news, msgs), Hamilton decided a solution was needed. GreenPrint produces software that eliminates unnecessary text or pictures -- such as Internet ads or big photos -- from printouts, saving both ink and paper. Besides making less waste, it saves money. "Ink is now one of the most costly liquids on the planet, about $10,000 per gallon," says Hamilton, whose product was launched in December 2006.

*Was 29 at time of selection

• Go back to Nos. 24-25

• Go to No. 27

• Return to the full list

Source: Inc.com

More from MSN Money and Inc.com

• More on the 30 coolest young entrepreneurs
• 30 under 30: In depth
• The best states for doing business
• The next big ideas
• The billionaires you don't know
• Start-up secrets from young entrepreneurs