Kwabena Boahen is working to create a computer that will fulfill his boyhood vision—a new kind of computer, based not on the regimented order of traditional silicon chips but on the organized chaos of the human brain. Designing this machine will mean rejecting everything that we have learned over the past 50 years about building computers. But it might be exactly what we need to keep the information revolution going for another 50. The human brain runs on only about 20 watts of power, equal to t