Using the ac adapter from an old parallel port external Zip drive and a USB to PS2 mouse adapter, I made this Ipod charger.
Step 1: Parts and Tools
I used the AC/DC power adapter plug (5.0V DC output) from an old parallel port zip drive, and the ps2 adapter that came with my USB optical mouse. Two things I'll surely never use again.
The tools I used were a sharp knife, an electric multimeter, soldering iron and solder, a pair of diagonal wire cutters, and some wire strippers.
Step 2: Cutting Away the Dead Wood
The hardest part of this project, and the only place where you can make a mistake!
Obviously the zip power supply should not be plugged in unless we are ready to test it with the multimeter.
First we'll prepare the (unplugged!) AC/DC power supply. Clip off the DC plug end, split the wires back about 1" being careful that the wires are both individually insulated (not exposed), and strip them, exposing ~1/4" of wire.
Check again to make sure that you haven't somehow left the adapter plugged into the wall, and if not, grab the bare wire, and twist it with your fingers to make it nice and tight.
*danger* During this step under no circumstances let the bare wires touch *danger*
*warning* Be familiar with the proper use of your multimeter *warning*
Set the multimeter to measure DC Volts, and test the wires with the adapter plugged in.
Once you have determined which lead is positive and which is negative, write it down.
If you get it wrong, you may damage your Ipod, and that would suck.
Now to prepare the PS2 to USB adapter, you'll need a sharp knife.
Slice the outer plastic on the adapter from the PS2 end of the adapter to about 1/2" from the USB end, pull it open, and cut away the epoxy glue and wires inside leaving only the soldering lugs on the back end of the USB plug. This may require the diagonal cutters again, but I did it all with a sharp pocket knife.
Also, don't cut yourself like I did.
The picture below shows the pinout for a male USB plug, like the one at the end of your Ipod adapter. It's probably best to clip off the data lugs (middle two) before proceeding to the next step.
Step 3: Assembly
Looking at the the diagram from the last step, you should be able to find the top of the female usb end, so that we don't get our wires crossed. On the male end pictured the contacts are upwards, on your female end, in the adapter you just butchered, up is with the contacts facing down. Be sure you have it right before you solder your positive wire to the +5V lug and the negative wire to the ground lug. Run the wire right through the old ps2 mouse plug hole!
Test it with the multimeter before you plug in your Ipod!
Now you can fill the void in the usb adapter with silicon glue, j.b.weld, epoxy or whatever you prefer, and it's completely tricked out!