off-the-shelf Power Distribution boards and harnesses

kkmulticopter.kr:  $7.00
"Switch included.  Thickness: 1.6mm
Switch slot length: 7mm  Hole distance: 45mm
Weight: 12g
This kit is compatible with MikroKopter components."

aeroquad: $17.95
"Very simple, yet solid power harness design for you to confidently put your quadcopter design together.  This has four power/ground wires for each of your motors, plus one plug for your Arduino / AeroQuad Shield and two additional plugs for things like powering external LED's.  The blue plugs are EC3 connectors which includes 3.5mm bullet connectors with the blue plastic hood.  All mating connectors are provided to give you a complete solution."

jdrones: $12.00
"Power Distribution for Quad Copters
Includes:
    * Power Distribution PCB (Rev.D)
    * 20 Pin 90 deg Pin header
    * 4 pin 20 awg signal cable
    * 2 pin 20 awg signal cable"