Many decried the original Game Boy Advance's reflective LCD screen and its reliance on external light sources. The Game Boy Advance SP's main feature--optional backlighting--fixes this complaint nicely, but it's the wealth of other features that makes this system so surprisingly good.
At first look, you might think the SP is a sleek travel alarm clock. When closed, it's just as tall and deep as the original GBA, but only half as wide. Due to its clamshell design, the screen is always protected from everyday scratches. A small button in the center of the console turns on the backlighting element for use in low-light situations, like in a moving car.
The SP comes with a well-designed power adapter that recharges a built-in battery; its prongs fold in for easier storage. Our informal tests found that it takes about four hours to fully charge (you can even play it while it's plugged in and charging), and the battery lasts about 11 hours with the backlighting constantly on--your results may vary. Using the backlighting less often will conserve battery power.
With separately sold cables, you can connect the Game Boy Advance SP to other GBAs for multiplayer gaming (above) or to the Nintendo GameCube (below) to access secret levels, exchange data, or use other special features that vary from game to game. The quality of the backlighting is very good. It's bright and clear when looking directly at it, but degraded from other angles. This is only a problem for friends who are watching the screen from over your shoulder.