1-Ryobi 18vdc Flashlight model P700 (Home Depot approx. $13)
1-7812 12vdc Regulator (Radio Shack approx. $2.00)
1-Bell 12vdc Power Clip Adapter (Advanced Auto approx. $6.00)
6" of red and black wire (you can use the extra wire from the power clip or some old speaker wire)
3- 1/2" lengths of heat shrink tubing (Radio Shack)
1-18vdc Ryobi Rechargeable Battery (you should already have this)
1-5vdc Power Adapter for Ipod or cell phone (you should already have this)
1- Drill and 1/4" bit
1-Roll of solder
1-Heat Gun (to shrink the heat shrink tubing, or you can use a match-be careful!!)
Step 1: 2 Uses in 1
IMPORTANT: The regulator used has a 1 amp limit so pay attention to how many amps you device requires.
IMPORTANT: You need to use a 12vdc to 5 vdc adapter to charge the smaller devices, you probably already have these in you car anyway!
Step 2: 12vdc Out
Step 3: 12 VDC Regulator
Step 4: Wire It Up!
Step 5: Don't Forget the Adapter
My apologies for not taking photos of the inside of the flashlight but you know how it is when you're building, you can't get it done fast enough.
Hopefully this is pretty self explanatory.