This idea stayed in my mind for the whole day, and once I finished cleaning my desk (you now all know it took a whole day) I gave a try at turning it into a usb-charger.
It was easy, I used 2 metal pins, one cm of perforated board, a old usb cable and 2 ml of solder... and it worked !!
I hope you'll like it !
I posted it since I couldn't find that anywhere else so I though I might share that info with you. It's not really powerful as a charger (320mAh) but it does the job and it avoids me from buying one.
Here are the pictures !
The top notch connector

The cable itself

Plugged in the NDS Charger

Charging my Ipod !

I hope you'll like it !
Done in 15 minutes (including soldering iron heating up
FG