Logitech Cordless TrackMan® Wheel $41.91

Here's a trackball that fits comfortably into your right hand, with its buttons and scroll wheel at your fingertips and a smooth trackball right underneath your thumb. It's cordless, so you can put it just about anywhere on your desk within six feet of the receiver. And it uses optical technology, not wheels or rollers, to deliver smooth tracking with virtually no cleaning or maintenance.

Buy.com is carrying this Cordless TrackMan® Wheel for $41.91