Present life: Cofounder and chairman of Wind River Systems, a 19-year-old, $305-million embedded-software provider in Alameda, Calif.

Former life: Professional guitarist and composer (while a grad student at the University of Illinois at Urbana-Champaign in the mid-1970s). After majoring in music, Fiddler sought a job as a resident composer at the university. He needed an advanced degree to qualify, and he was curious about computer-generated music, so he pursued one in computer science. "Champaign is a small but wonderful musical community with lots of independent dance companies in town," he says. "It's also at the north end of the Bible Belt, so there was work playing for the record labels doing gospel albums."

Lessons learned: Fiddler believes his experience with composing made him a better programmer. This was especially important in the early 1980s, when he was still writing most of Wind River's software. "In both cases you're building a complex structure in your head to meet certain constraints," he says.

Fiddler still relies on the improvisational skills he developed as a jazzman. "Running a company is like jazz because of the changing environment and changing people. I'd never say it at a business meeting, but that's what you're doing -- you're jamming," he says. Last April, when Wind River's CEO abruptly resigned, Fiddler jammed for a while as pro tempore CEO. He sliced Wind River into business units and set $1 billion as a revenue target for 2004.

"In jazz you have a theme, chords, a bass line, and rhythm that define what you can and can't do, but lots of freedom within that. I felt secure making the changes, because we knew our theme and basic structure," he says.