If you're like most cyber-citizens, you use the Internet for e-mail, Web searching, chatting with friends, music downloads, and buying books and gifts. More than 600 million people use these services worldwide-far more than anyone could have predicted in the 1970s, when the Internet's key components were conceived. An estimated $3.9 trillion in business transactions will take place over the Internet in 2003, and the medium's reach is increasingly global: an astonishing 24 percent of Brazilians, 30 percent of Chinese, and 72 percent of Americans now go online at least once per month.

Still, despite its enormous impact, today's Internet is like a 1973 Buick refitted with air bags and emissions controls. Its decades-old infrastructure has been rigged out with the Web and all it enables (like e-commerce), plus technologies such as streaming media, peer-to-peer file sharing, and videoconferencing; but it's still a 1973 Buick. Now, a grass-roots group of nearly 100 leading computer scientists, backed by heavyweight industrial sponsors, is working on replacing it with a new, vastly smarter model.