The 2008 TIME 100

If the brain is science's great frontier, you need someone to lead the expedition—someone with smarts and curiosity, not to mention a large bank account to finance the journey. In the terra incognita of the brain, that's Paul Allen.

Co-founder of Microsoft, owner of three sports teams and lead backer of SpaceShipOne, which in 2004 made the first private manned space flight, Allen, 55, is also head of the Allen Institute for Brain Science, which was founded in 2001 with the goal of mapping the brain, cell by cell and gene by gene. His scientific team began with the mouse brain and finished the job in 2006, posting all the data online. Scientists everywhere now have a free neural GPS to learn where and how specific genes are expressed—a vital tool for studying similar functions in human brains.

The institute has now begun its own effort to map human gene expressions, hoping for insight into the molecular basis of consciousness and creativity. Allen founded his institute in the belief that with the right tools you can transform the speed of science itself. Not many people accomplish that even once. Allen is doing it yet again.

Insel heads the National Institute of Mental Health; Landis leads the National Institute of Neurological Disorders and Stroke