J. Craig Venter's Next Little Thing:

The man who mapped the human genome has a new focus: using microbes to create alternative fuels.

J. Craig Venter, maverick biologist, wants to cure our addiction to oil. To do so, he proposes creating a designer microbe -- the heart of a biological engine -- from scratch, then adding genes culled from the sea to turn crops such as switch grass and cornstalks into ethanol.

While he's at it, he'd like to modify or devise microorganisms to produce a steady stream of hydrogen.

Either could prompt a major shift in the economics of the energy industry and in the process bring Venter to a secondary goal: showing the world he can be as successful running a company as he was at sequencing human DNA.

"We are on a crusade as much as it is an economic goal," Venter said. "This is one of those crusades that only works if it becomes really profitable."

Five years after antagonizing government scientists while racing them to map the human genome, Venter is back, making the typically bold statements that have long polarized opinion about him. Either he is one of this era's most electrifying scientists, or he's one of the most maddening. He is apt in conversation to compare himself to Robin Hood. Or Darwin.

"Yes, Craig confronts," said Alfonso Romo Garza, a Mexican billionaire, controller of a decent chunk of the world's commercial vegetable seeds and a backer of Venter's latest undertaking. "Of course, he's antagonistic. He's controversial. But I love controversial people because those are the people who change the world."

Bearded from a three-year, Darwinesque yacht trip around the world, Venter also now sports an extensive collection of genetic material scooped from the sea on his journey -- and that's the raw material for his alternative fuel project. With $15 million from Garza, he has launched a new company in Rockville called Synthetic Genomics Inc.

It is a small firm with classic Venter ambition. Create life. Use it to make fuel.

There are caveats, to be sure.

Venter's business career made him rich, but his record running Celera Genomics Corp. was spotty. The company's original business plan -- selling access to the genetic data Venter helped develop -- faltered because the information became public through the government's efforts.

Celera has since waxed and waned with other business plans that haven't yet worked out.

He insists this time that things have changed.