This shows how to power an LED or some Christmas lights from the USB port on your computer.
Step 1: Get Your Materials
For this you will need the following:
Old USB cable with a male end (like an extender that you can buy at the dollar store)
An old set of battery operated Christmas lights (also a dollar store product)
Step 2: Get Out Your Wires
Cut one end of the USB cable off. You may wish to give yourself as much cable length of the male side of the cut cable. there are 4 colored wires inside the large wire. expose the red and black ones. these are the power wires that would power the USB device. the white and green ones are for information transfer and aren't used.
A USB cable puts out about 5 volts of power, just enoguh to power most LED's and battery operated Christmas lights (they usually take 2 AA or D cell batteries which are 1.5 volts a piece. 2 batteries = 3 volts, so a USB cable has more than enough power but not too much)
Step 3: LED
The LED has two legs the long one is positive (+) and the short one is negative (-). The wire from the red coated wire from the USB cable is the positive, wrap that one around the long leg of the LED. (if you have money you can use a soldering iron) and wrap the wire form the black coated wire around the short leg from the LED. put tape or something of the like on one leg to prevent crossed wires ( it can cause a spark, personal experience) plug the USB cable into your computer and it will light up. Simple.
Step 4: Christmas Lights
The same applies with the red and black coated wires here. Take the battery pack from the Christmas lights and snip it off. strip the wires.plug the USB cable in and touch the wires from the lights to the red and black wires, striped. when the lights light up, unplug the USB and twist the wires together. tape one of the wire connections to prevent crossed wires. There you go!
Step 5: Enjoy
this is a neat project to spice up any computer area. if the USB cable is left plugged in, when the computer turns on and off the lights will light up with the computer. it is nice to turn on your computer and have your desk light up! Also, this was my first instructable and hopefully, they will get better from here on out =P