Their are plenty of USB fans on here but not quite like this one.
This fan can be made (with the addition of E-Tape) compleatly out of the insides of an old computer. So don't just throw those headakes away smack em with a hammer or something, and see what you can scanvenge from the inside, ok so mabet don't hit it untill you get the stuff out that you want. That includes stuff like cd drives, hard drives, cards, processors, cables and power supplys, if you can use it take it. Also an X-acto nife, sisors, and small plyers are a help. (would have used shrink tube but I was out at the time)

AND IF YOU DON'T ALLREDDY KNOW USB PORTS SUPPLY 5 VOLTS WHILE THE FAN(S) ARE USUALY 12. SO IT WILL BE UNDER POWERED. AND NO COMPLAINING/ARGUING ABOUT IT BECAUSE THE IMFORMATION HAS ALLREDDY BIN POSTED!

Step 1: Materials

Well not much to explain here.

SO the stuff that you will need is as follws:
1X Fan
1X Usb Port
1X Sound Cable
1X Role E-Tape
1X X-ACTO Knife
1X Sisors
1X Plyers/Wire Cutters

Step 2: Ok You Got Your C**p Now Get to It!

First were going to plug the USB thigy in to the port of the pc. Now we can check the polarity of the fan.(not exactly nessary if it runs both ways) But go and tuch the red and black wires to pins 1&4. Pin 1 is positave and pin 4 is negative. [take note of this for later and other instructables].

Ok since you'v done that you can connect the sound wire to the USB plug, i was able to just kinda plug them togather like an extenshion cord or something with the en that goes in to the CD-Drive and then tape it up. You now have one part of the cable prepared to connect to the fan, woo!
Make shue you know witch wires are + and -. You can just cut off the extra wires that you dont kneed, but I thought that there culd be risk of a short so i left the wires I dident kneed and individualy wrapped them with tape so that the ends culd not tuck thus causing a short that culd either dammage the port/computer or cause the pc to reboot/shutdown

Step 3:

Ok so we have one side done so here's about the other end.

Make shue you know witch wires are + and -. You can just cut off the extra wires that you dont kneed, but I thought that there culd be risk of a short so i left the wires I dident kneed and individualy wrapped them with tape to the main wire so that the ends culd not tuch thus causing a short that culd either dammage the port/computer or cause the pc to reboot/shutdown.

Now if your cable was like mine the red and black wires turned out to represent their respective charges + and -, I was also able to attack the red and dlack wires of the fan to the cable togather
(R-R,B-B). NOTE: when attaching the wires it is best to twist the ends individualy the same directionand then joining the the others to the same color, again twisting in the same direction.

I attached the wires so thatthe fan and plug wnet the same was from the splice, i then folded the fan wires so they went on top af the splice where i then made the final wrapping of tape!

well there you go use it fo whatecer you want, I use mine to cool my notebook (it's a few years old and gets really hot!)