NextWarehouse offers the BIC America F12 12" 475-watt Powered Subwoofer for $183.40 with free shipping. (Provantage has it for pennies more.) That's tied with our September mention and the lowest total price we could find by $6, outside the price below. This front-firing subwoofer features adjustable crossover, adjustable volume control, and automatic signal sensing.
A close price: Amazon offers it for $184.22 with free shipping.