Cambridge, Mass.

In 2005, Nicholas Negroponte unveiled an idea for bridging the technology divide between rich nations and the developing world. It was captivating in its utter simplicity: design a $100 laptop and, within four years, get it into the hands of up to 150 million of the world's poorest schoolchildren.

World leaders and corporate benefactors jumped in to support the nonprofit project, called One Laptop Per Child. Mr. Negroponte, a professor on leave from the Massachusetts Institute of Technology, hopscotched the world collecting pledges from developing nations to buy the laptops in bulk.

But nearly three years later, only about 2,000 students in pilot programs have received computers from the One Laptop project. An order from Uruguay for 100,000 machines appears to be the only solid deal to date with a country, although Mr. Negroponte says he's on the verge of sealing an order from Peru for 250,000. The first mass-production run, which began this month in China, is for 300,000 laptops, tens of thousands of which are slated to go to U.S. consumers. Mr. Negroponte's goal of 150 million users by the end of 2008 looks unattainable.

Mr. Negroponte's ambitious plan has been derailed, in part, by the power of his idea. For-profit companies threatened by the projected $100 price tag set off at a sprint to develop their own dirt-cheap machines, plunging Mr. Negroponte into unexpected competition against well-known brands such as Intel Corp. and Microsoft Corp.'s Windows operating system.