The 3M EM500 Ergonomic Mouse looks so much like a joystick that we initially thought we'd be moving the mouse around by tilting the mouse's vertical grip. But looks can be deceiving: the EM500 Ergonomic Mouse functions by dragging across the desk surface, just like a traditional mouse. The unique vertical grip is designed to keep your hand, wrist, and forearm in a neutral upright position--much like a handshake--that eliminates the forearm twisting that is blamed for some repetitive stress injuries. (Of course, if you are experiencing repetitive-stress-related discomfort because of using your computer, you should seek out the advice of a doctor in addition to making adjustments to your workstation.)
Aside from its unusual design, everything about the EM500 Ergonomic Mouse is simple. To use it, just plug it into your computer's USB port (or a PS/2 port using the included adapter)--no software is required, though we had to increase the mouse sensitivity in the Control Panel to account for the unique shape. You navigate by resting your hand on the base, loosely grasping the vertical grip, and sliding your hand from side to side to move the cursor. There are just two buttons on the EM500: a rocking thumb button and a broad button at the fingertips. The former functions as traditional left- and right-clicks (press down for left-click, up for right-click), while the latter functions as a center-click and scroll key. Unfortunately, these buttons are not programmable.
