Best Buy offers the Logitech M510 Cordless Optical Mouse in Light Silver (pictured), model no. 910-001822, or Blue, model no. 910-002533, for $19.99 with free shipping. (Amazon has it in Light Silver for the same price.) That's the lowest total price we could find by $10, although we saw it for $2 less in February. This wireless mouse features a USB nano-receiver and ambidextrous, ergonomic design. Two AA batteries are included.