TigerDirect offers the Klipsch HD 500 5.1-Channel Speaker System, model no. HDTHEATER500, for $279 with free shipping. That's the lowest total price we could find (outside of the mention below) by $90, and the best deal we've seen for this system since February 2011. The Klipsch HD 500 includes five Klipsch speakers, which contain a 2-1/2" woofer and a MicroTractrix horn-loaded 3/4" aluminum dome tweeter, plus an 8" 100-watt powered subwoofer.

A close price: Amazon has it for $279.99 with free shipping.