Digital Outlet via eBay offers the open-box Logitech G100s Optical Gaming Mouse, model no. 910-003533, for $11.99 with free shipping. That's $3 under the best total price we could find for a factory-sealed unit. It features an ambidextrous design and 250 dpi to 2500 dpi tracking resolution.

Note: This item is new but will not ship in the original packaging.