Found these interesting companies from the New York Times. One deals with energy, and the other deals with manufacturing.

Bloom Energy. The company is developing a solid-oxide fuel cell that it believes “could generate more than enough electricity to power a house.”

MFG.com. This is basically 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.”