Belkin’s Washable Mouse is a water-resistant mouse that can survive spills and can be hand-washed under the faucet to stay clean.
Of course, this washability doesn’t come at the cost of features: The mouse employs an optical engine with 1200 dpi for high sensitivity that works on many household surfaces, including upholstery, glass, and wood. A scroll pad allows both vertical and horizontal scrolling with one easy touch.
Washable Mouse at CES 2008 Video
You can buy it at Amazon for $29.99 [link]