Microsoft Wireless Intelli Explorer (M03-00044) Mouse

Pros: Dirt cheap, optical, decent battery life, many ugly designs to choose from
Cons: Hard-to-press buttons, tilt-wheel, and mouse shape are all anti-ergonomic. No tactile feedback on scroll wheel.

Unlike with previous corded+wireless duos from Microsoft, the IntelliMouse Explorer 4.0 and Wireless IntelliMouse Explorer 2.0 are virtually identical--except for the cord. A Match Made in Heaven Until about a year ago, you could have more ...

Pros: Hook-up is fast and easy
Cons: Material used on the sides of this mouse seems to be defective.

Mouse sat on desk several months unused. Decide to use again.
Rubber (both) sides are sticky. Sticky won't wipe off.  Not just a spot or two but down the whole left and right side of mouse. I've never seen anything like this. No one has ever touched it but me and I am very particular about my computer equipment. It reminds me of a blacktop road in the summer when the sun is blazing down on it and the surface gets sticky. Now it's unusable because my thumb and fingers stick to it. Nothing has ever been used on it except a damp rag.