Crutchfield offers the JL Audio 6.5" 4-ohm Subwoofer, model no. 6W3v3-4, for $143.99 with free shipping. (Abt and Sonic Electronix charge the same.) That's the lowest price we could find by $16. It features a mineral-filled polypropylene cone, 40- to 150-watt RMS power handling (300-watt peak), and frequency response of 30Hz to 300Hz. Deal ends December 3.