Ten years ago, even though he was on the fast track at Siemens in India, Santosh Kumar abruptly quit. Coming up with code for telecom switches was not how he wanted to spend his life. Instead he moved to the U.S. to pursue a Ph.D. in computer science. He had an idea for inexpensive, low-power wireless sensor technology and how it might solve serious real-world problems. His leap paid off. Now a professor at the University of Memphis, he develops tracking systems that can foil robbers and might even help cure drug addiction.