The usb penstyle I made from your pictures still works. I have been using it today also on my i-pod charger works good still, even though I said it not
as powerfull from computer usb port.
Making the battery component to a wired device is easy.( for the pen model) just pop off the grey cap. Stick some needle nose plyers into it pull out the battery. Then with the round part on the needle nose plyers (becarefull) pull out the screw part, cut the electronics off of it. than solder a wire in the inner middle part of the screw, make sure you put the wire through the tube first. Then put it together. With a piece of metal rub the paint off of the tube, make sure you rub quite hard because you want the solder to beable to stick to the metal. You'll need a switch, I used simple on off switch from a phone. Then solder one of the correct contacts to the outer part of the tube along with the other wire your going to attach to the usb (I used speaker wire to extend the distance..lol) wire red and black.
and there ya have it!