As one of its daily deals, Best Buy via eBay offers the JBL CX Series 12" Single-Voice-Coil 4-ohm Subwoofer for $29.99 with free shipping. That's tied with our mention from two weeks ago, the best price we could find by $30, and a very low price for a JBL 12" subwoofer. Deal ends today. Features include:

polypropylene woofer cone

1,000-watt peak power handling

35Hz to 200Hz frequency response

90dB sensitivity