Kensington Expert Mouse Wireless

Die-hard trackball users swear by rolling a ball around with their fingers, rather than using their whole hand to push a mouse--and they claim they can never go back. Why? Some trackball fans prefer the way you can keep your hand fairly open as you move the ball around, as opposed to the gripping or holding sensation that a conventional mouse demands. If you're already an old pro at trackball maneuvering, the pricey $120 Kensington Expert Mouse Wireless gives you the same mousing experience, minus the cable. You don't eliminate all the cables, however--the unit comes with a USB-based corded RF transceiver, which sits on the desk. You get a wrist rest attachment, as well.

If you're a mouse user who wants to make a switch, be aware that trackballs require a lengthy adjustment period. Testers who were accustomed to regular mice reported that the Expert Mouse Wireless felt uncomfortable at first. (In fact, some people who try a trackball never get comfortable with it, despite giving it their best shot.)

The device is shaped like a big box that slopes upward, with a large, smooth ball sitting on top. This sloping design makes hands of any size bend at the wrist, generally considered an ergonomic no-no. The wrist rest helps ease the discomfort a bit, but it's not big enough for all users. One tester with big hands and long fingers complained that it was too short, as his palm tended to rest on the outer edge of the pad--not exactly cushy. In addition, reaching the top two buttons can be a bit of a stretch over the ball, for short and long fingers alike.

By default, the top two buttons are forward and back buttons for Web navigation, and the two lower buttons are the right- and left-click options. The scroll wheel surrounds the ball--you move it up and down--and is easy to use. Kensington's software makes customization simple; you'll find options for all the buttons in the Kensington MouseWorks utility. For example, you can set a keyboard shortcut that switches the movement of the ball to a very slow speed, which would be very useful for detailed work. A bonus for lefties: You are presented with a check box that lets you swap your settings in an instant.

When we first started using the trackball, which employs optical tracking technology, the ball itself seemed sluggish, but its performance improved after a few hours of use. The ball's surface is supersmooth, so you may have to work extra hard on moving the pointer around, depending on how slick your fingertips are. That said, both the ball and the circular scroll wheel move quietly without any rattling sounds.

Kensington says that the two C batteries included in the package should last six months.

Switching to a trackball takes some getting used to, and this Kensington model is the most expensive mouse we've tested. But you get plenty of customization options if you want to change the defaults--and you get a unique mousing experience, as well.

Aoife M. McEvoy