Within the next 12 months, as many as 10 million laptop computers will be distributed to children in Argentina, Brazil, Libya, Nigeria, Pakistan, Rwanda, and Uruguay. Countless youngsters who live in remote villages, perhaps without electricity, who may not have access to clean water or health care, will suddenly have computing power pretty close to that of businesspeople and college students.

It's one of the biggest nonprofit technology-based projects in a decade, and yet it's only the first phase of a program that seeks to put a staggering 100 million laptops into the hands of developing-world schoolchildren in the next couple of years, at a cost of at least US $10 billion. By any standard, the numbers are enormous: 100 million laptops is double the number produced annually throughout the world today. Simply meeting that target would almost surely cause global shortages of liquid-crystal displays and other key components.

The initiative, known as the One Laptop Per Child (OLPC) project, is the brainchild of Nicholas Negroponte, the founder of MIT's Media Lab, who announced the project at the World Economic Forum in Davos, Switzerland, in 2005. Hardly anyone questions the worthiness of the project's goals, but just about everything else about it has been fair game.

First, there are the technical challenges: designing a computer that's rugged, useful, superefficient, and cheap enough for the Libyan deserts and the Brazilian rain forests isn't easy, to put it mildly. In fact, it has forced the One Laptop team, with its abundance of former MIT engineers, to reinvent the portable computer as we know it.

Then there are the social and logistical issues. The project is counting on teachers, who may or may not welcome these electronic replacements for books. Money for the laptops will come out of already tight government budgets and will mean that other, perhaps better, government programs will lose funding. Theft of computers will undoubtedly be a problem, as will repair and maintenance. And what will happen when millions of computer-literate teens graduate into low-tech societies? Nobody knows. Nobody is even trying to find out.

Sometime next year, if all goes according to plan and the organization is selling millions of laptops every month, economies of scale are supposed to bring the manufacturing cost of an individual laptop down to $100. It's now somewhere around $150. From that gallant goal has come the program's informal identification as the $100 laptop project.

The One Laptop effort is just one of at least 20 low-cost computing initiatives under way worldwide [see the online sidebar, ”Other Roads to Computing for All”]. But it's the biggest, best-funded, and most hyped of all the initiatives, so it's the one that will almost certainly determine whether the mass distribution of PCs to children becomes an enduring component of national development or just another well-meaning but ultimately misguided experiment in social engineering.

Without a doubt, Negroponte has captured the world's imagination with the $100 laptop. Since his 2005 announcement, he has worked the international media to develop momentum for the project, even conducting demonstrations of the device for global figures like Kofi Annan, former secretary-general of the United Nations. In 2006, the project spun out of MIT into a nonprofit called One Laptop Per Child. That June, the team demonstrated a working proto type. The pilot phase of the project, just getting under way now, promises to roll out at least a million laptops in each of at least five different developing nations.

As of January, the OLPC team believed it had brought on board at least seven countries. Commitments in this arena are notoriously fungible; people rise and fall in government power structures, and a commitment made by one official may not be honored by others. Still, Michail Bletsas, chief connectivity officer for the organization, says OLPC has more than reached its goal of 5 million orders for delivery in the first year--that is, by early 2008.

Those who have struggled for years to bring the developing world into the Internet age are watching these efforts closely. For the most part, they are thrilled about the technology but are worried about the sales strategy, which is to sell the PCs in lots of 1 million to national ministries of education for deployment throughout national school systems. The ministries are using funds that otherwise would go to buy textbooks, leading some wags to declare that it's a ”$100 million laptop,” not a $100 laptop.

And, typically, schools in developing countries are already struggling with an array of problems--overcrowded classrooms, incompetent or absent teachers, and a lack of textbooks, chalk, and other basic materials. ”It's right out of Alice in Wonderland,” says Atanu Dey, chief economist for Netcore Solutions, in Mumbai, India. ”When Alice meets the Cheshire cat, she says that she's seen a cat without a smile but never a smile without a cat. I've seen a school with teachers, blackboards, and books without laptops, but I've never seen a school with laptops but without teachers and the rest.”

Others worry that theft or government corruption will mean money will be spent but laptops won't get to students. And even if the computers are properly distributed, it's easy to imagine that some teachers may become miffed when their more computer-literate students start using their laptops to chat and pass notes during class (they're all wireless-equipped).

Says Lee Felsenstein, chief technical officer of Fonly, a product development firm in Palo Alto, Calif., and a pioneer in personal computer design, ”The kids will pass notes. It happened in college lecture halls, and the teachers turned the wireless network off, because no teacher allows the passing of notes in class. Likely, the laptops will be banned from classrooms.”

The computers are engineering marvels. So far, preproduction models have been built. Each rugged, self-networking unit has a screen that is readable in darkness or full sunlight. ”The technology is clock-stopping hot,” says Wayan Vota, director of International Executive Service Corps Geekcorps, a nonprofit organization that works with information and communications technologies in the developing world.

These $100 laptops (well, okay, $150 laptops) have capabilities beyond those of units costing 10 times more. The first-generation product is equipped to function not only as a fully featured laptop but also as a game console, a home theater, and an e-book. In practice, this diversity of uses means the user must be able to fold the screen back against the top of the computer, to hold it like a book, as well as to stand the screen up perpendicular to the keyboard to share it with groups.

Designers made this kind of flexibility possible by mounting the motherboard directly behind the screen. As a result, the hinge contains only the wires to the keyboard, not the large number of fragile connections embedded within a traditional laptop hinge. It's just one of several clever innovations that address the computer's unique niche.

In the developed world, most laptops are traded in for new ones every few years. But the youngsters in the OLPC program will be driving theirs, so to speak, for the computer equivalent of 500 000 kilometers. And they are, after all, kids, so their computers need to be as close to indestructible as possible. The models going out now have a 2-millimeter-thick plastic shell, compared with the 1.3 mm used for most commercial machines. When folded, the laptop seals with a rubber gasket, to keep out water and dust. The rubberized keyboard also helps protect the innards from liquids and dirt.

This model does without the three components that most frequently fail in laptops: the hard drive, the cooling fan, and the monitor screen's fluorescent backlight. Lacking a hard drive, the system will store its 130 megabytes of applications and operating system plus any documents on 512 MB of flash RAM. Light-emitting diodes will illuminate the display, and the designers decided that with a low-power processor and no hard drive, they could get by without a fan. Even in hot environments, this lack of a fan is not likely to be a problem, says Felsenstein.