Best Buy offers the Microsoft Sculpt Ergonomic Wireless Mouse, model no. L6V-00001, for $28.99 with free shipping. (Amazon charge the same price.) That's the lowest total price we could find by $2, although most stores charge $45 or more. It's shaped to assist with correct hand posture, and features seven buttons, a four-way scroll wheel, 1,000 dpi movement resolution, and a wireless range of 10 feet. It requires two AA batteries (included).