Stock RBK headunit, 360 watt Lanzar (it *****, but it was $40 shipped off ebay!) and a 10" Kappe Perfect in a .6 cu ft sealed box. It does OK.
Box velcros to the floor and has a hook that grabs on the anchor behind the seat. I can have it removed for extra storage in less than 15 seconds. I also put an on/off switch for the amp up in the dash so I can kill it (wife hates bass), and so I can leave the speaker wires hanging without fear of them shorting. Lanzar Amp fits perfectly under the driver's rear seat, totally stealth.
I'd like to pick up a better amp, hopefully sooner than later. Laugh all you want, but I miss the old 1st gen Sony Xplode that I had prior to this - I fried it out as it was too old and I overdrove it. I'd like to pick up another - they are cheap and it sounded good enough for me. This Lanzar is crap.