For this project you will need:
1 - Male USB plug (got mine from a $1.50 Wii Intercooler)
1 - 22 ohm resistor (red-red-black) thats all I had, dunno if its perfect
1 - LED
Hot glue (optional)
Sorry about the bad pics
If you do anything wrong and screw up your computer, burn your finger etc etc...I'm not responsible!
It's a very easy project, but things could go wrong,
Step 1: Extract the USB plug
Step 2: Marriage
First, solder the ground on the LED to the ground on the USB plug.
Now solder one end of the resistor to the +5 volt plug (power) of the USB port, solder the other end to the positive lead of the LED.
Step 3: Test and Finish
If you want, you can put hot glue around the connections to secure them. I did because my stuff always breaks.
That's it! Go light up a computer!