So I'm not really sure if I'm allowed to post this on here, but Best Buy has a Polk sub as their deal of the day. It's only 30 dollars as the title says. I thought somebody on here might be interested. The deal ends at midnight though.
Polk Audio - 12" Single-Voice-Coil 4-Ohm Subwoofer - Black - DXi124 SVC
I hope this helps someone out that's looking for a new system.