ng this [system] right now to see if people are willing to pay the extra cost," says Locker. Many people are also looking at portable systems other than notebooks. Tablet PCs may be an alternative for many users, particularly those who need to work with large amounts of text or numeric data in mobile environments. The systems, which are designed to mimic the dimensions of a large paper notebook, include an operating system that lets users jot information with a pen-like stylus. Mike Stinson, vice president of mobile products for Gateway Computer, predicts that pen-based input will be "a requirement" for most portable system users by 2005. "It's just an easier way to take notes," he observes. Tablet PC shipments in the United States are set to climb from 260,000 units in 2003 to 2.25 million in 2005, according to statistics compiled by IDC, a technology research firm (and CIO Magazine sister company). State-of-the-art PDAs are also gaining traction in many enterprises, thanks to their low cost, small size, wireless connectivity, and miserly power consump- tion. Busy managers appreciate the devices' ability to handle a variety of simple tasks, ranging from e-mail to text entry. Whether people rush toward notebooks and other mobile devices, a shift toward smaller PC forms seems inevitable. A growing number of enterprises are looking closely at thin-client devices, says Martin Reynolds, a fellow at research firm Gartner, located in Stamford, Connecticut. Thin clients, which link to a central server and have no internal disk storage, hold the promise of lower cost, better management, and enhanced security. "The market is more ready for them now," says Reynolds. Although the thin-client model has existed for many years, Reynolds believes that in a chaotic world of viruses, hackers, and seemingly endless "critical updates," it makes more sense than ever to manage systems at the server level rather than on individual desktops. The PC world is rapidly marching from desktop- to device-based comput- ing-an environment in wh