For its Amazon Prime members, Amazon offers the Logitech M510 Cordless Optical Mouse, model no. 910-001822, for $20.98 with free shipping. (Non-members can spend over $25 for free shipping; otherwise, shipping adds $8.22.) Outside of the mention below, that's the lowest total price we could find by $11. (However, it was a buck less in November.) This wireless mouse features a nano-receiver, ergonomic design, and more. Two AA batteries are included.

Amazon Prime membership is $79 per year; however, Prime is free for college students for six months, and free for parents and caregivers for three months. (Note that there's a waitlist for Amazon Mom.)

Meanwhile, Fry's Electronics offers it for $17.99 plus $2.98 for shipping. (Free in-store pickup is also available.) Sales tax is added where applicable.