Laser can refresh your air by kill the bad bacteria and fungus in the air.You can make a cool lamp too. All with the usb power.
Step 1: Cut pc blade
cut all the blade on a pc fan,drill 4 hole on a moni dv disk and glued 4 laser
Step 2: Place plasric bottle on the machine
tape with black tape and let 4 hole for the air extraction,place 4 screw for making the leg of the machine
Step 3: Plug a usb cable
plug a switch and after take a usb cable and take the red and black wire for powering the machine
Step 4: Now just to put the switch on and see the beautiful light