Amazon offers the Logitech Z506 5.1-Channel Surround Sound Speaker System, model no. 980-000430, for $50.99. With free shipping, that's tied with our expired mention from three days ago and the lowest total price we've ever seen for this speaker system. (It's also a current price low by $30.) Features include 75 watts RMS power, down-firing subwoofer, 45Hz to 20KHz frequency response, 3.5mm audio input, and more.

Note that this item will be in stock on September 3.