Installed the '07 version of my light system this weekend. Added a second Whelen TIR III in back. The pair of them are so bright I'm wondering if I may be breaking some regulation. The gory details:

Front bike rack: Rivendell Mark's Rack
Batttery: 5AH SLA, I get about 30 minutes on full bright, but with the dimmer I can do the whole ride.
Battery Box from Target, I'm using Bungees this year to get a bit of suspension between the rack and box.
Light Dimmer Circuit: Light Brain 2002 twin
Dual Auto style fog lights, with 20 Watt Halogen MR16 bulbs, one narrow, one medium spread.
All connectors upgraded to Power Poles.

In the rear:
Dual Whelen TIR III flashers, mounted on a 1/8 by 1 1/2 aluminum stock, attached to the rear rack with "P" clamps.

Plus:
Planet Bike Beamer, bar mounted.
AAA LED flashlight velcro'ed to helmet.
Backup AA batteries to run the flashers if the SLA goes dead.