Logitech Marble Mouse - Optical Trackball - 2 Button $18.99

The familiarity of a mouse with the convenience of a trackball. Designed for comfort in either hand, this space-saving trackball boasts Logitech's innovative optical tracking system to deliver superior precision and smooth motion with virtually no maintenance or cleaning required.

Buy.com is carrying this Optical Trackball - 2 Button for $18.99