With the publication this month of his long-awaited book, Telecosm: How Infinite Bandwidth Will Revolutionize Our World (Free Press, $26), Gilder has reached the apex of a journey from political visionary to technology visionary to just plain visionary. In his coming world, an abundance of fiber-optic communication channels will span the global economy, connecting "cathedrals of light" in which "angelic messengers" touch the lives of all. This is not a metaphor. As Gilder wrote in Forbes ASAP a few years ago, the 21st century, thanks to this broadband revolution, will be a "new epoch of spirit and faith" where life is lived in "the blazing light, majestic cumulative power, truth and transcendence of contemporary science and wealth, enterprise and adventure on the capitalist frontier."

In an America obsessed with spirituality and money, Gilder has found an influential and lucrative niche. He has been propagating his worldview, along with his stock picks, in his Technology Report since 1996. The monthly newsletter boasts more than 65,000 subscribers (at $295 per year) and has contributed a new phrase to the market lexicon: the "Gilder effect," in which the guru's pick alone is enough to send a stock skyrocketing. ("It's an awesome burden," Gilder says.)

His company is selling insights about several other subjects, as well. It puts out New Economy Watch and the Digital Power Report. A publication on semiconductors is scheduled to launch later this month and a fifth newsletter (on biotechnology) is in the works. In addition, Gilder is planning a magazine dedicated to discussing his philosophy at length. His conferences, sometimes run in conjunction with Forbes, are also hugely successful. October's Gilder/Forbes New Economy Conference in New York, for example, is charging $2,995 a head and will most likely sell out.

It's a pretty good business, and if history is any guide, it will only get better.

Gilder began his intellectual life as a conservative revolutionary at Harvard University in the 1960s. As a student of Henry Kissinger, he made connections in the nascent neo-con movement and ended up writing speeches for, among others, Richard Nixon and Nelson Rockefeller. He rose to national prominence as the author of the arch-conservative Men and Marriage in 1972 and Sexual Suicide in 1974 and went on to become an early and vocal proponent of the supply-side economics that famously inspired Ronald Reagan's political philosophy, if not his budgeting.

Gilder's Wealth and Poverty, a 1981 bestseller considered by many to be the supply-side bible, could be found on the coffee tables of intellectual conservatives throughout Washington, and Gilder became a favored adviser to Reagan. (Gilder claims Reagan quoted him more than any other living person during his administration.) Microcosm, Gilder's 1989 bestseller, anticipated many of the themes of the Internet Economy and assured him a place on any shortlist of high-tech visionaries.

Today, Gilder's various activities are run out of an organization called the Gilder Technology Group, the home of which is a graciously decaying mill hidden away in the Berkshire hills of Massachusetts. Sitting on the banks of the Housatonic River, the office is reachable only on narrow country roads. Cell phones don't work here, and the biggest crowd to be found is an occasional horde of antique-hunting Manhattanites.

Gilder himself is no less unpresupposing. The lanky 60-year-old is reputed to be something of the absent-minded professor, and sure enough, the laces of his black and orange sneakers are untied, his navy-blue jacket stained, his reading glasses misplaced.