The most highly evolved species of computer, the notebook (aka laptop) computer allows you to work without being tethered to an office. Portability and good performance make notebook PCs an essential part of the daily lives of millions, from college students to business travelers. Even the least-expensive of today's laptops are better equipped than they have ever been, and may be all you need for everyday work.

If you've ever shopped for a notebook, you know that the factors to consider go far beyond performance and connections. Notebook buyers also have to mull such variables as size, weight, screen dimensions, battery life, and keyboard quality--not to mention options such as built-in wireless

Before shopping for a notebook, consider how you'll be using it. If your primary goal is to get some word processing or spreadsheet work done while staying on top of e-mail, a $1000 low-end Celeron model with a 12.1-inch screen and 20GB hard drive will be plenty fast and save you hundreds of dollars. Sexy lightweight notebooks and models with top-notch processing power and big screens cost much more.

However, keep in mind that most vendors let you custom build and price your own notebook by picking from a mind-boggling array of features, which gives you a lot of control over the final product. You may be able to afford a faster notebook by accepting a smaller, less expensive hard drive or a CD-RW drive instead of a combination DVD-ROM/CD-RW drive.

Unlike with desktop PCs, you can later upgrade only some of these components, such as memory and the hard drive; others, such as the graphics board, are permanent once they're installed at the factory. That's slowly changing, as some manufacturers are incorporating upgradable graphics. However, take your time and pick only what you need. Below is a rough breakout of some configuration options.