Amazon offers Prime members the Logitech K100 PS/2 Keyboard, model no. 920-003199, for $9.95 with free shipping. (Non-members can spend $25 or more to qualify for free shipping; otherwise, shipping costs $9.) That's the lowest total price we could find by $6, outside of the price below. It features spill-resistant construction, and more.

A close price: newegg sells it for $9.99 with free shipping. Deal ends today.