I made this helmet in tribute to the group LMFAO for this past Halloween. It was surprisingly easy to make, and I think it cost less than thirty dollars to build. You can pick up all of the electrical parts at radio shack, although it is cheaper to get them online. Before attempting anything involving leds I would recommend reading http://www.instructables.com/id/LEDs-for-Beginners/
. I took some old cardboard boxes that I had lying around and used them to make a helmet. I then cut holes for the cup eyes. Below that I made the actual eye holes, which look like nostrils. I put black construction paper on the inside of the mouth. If I ever update this thing, I think I'll cut out the nostrils and false mouth and then cover that with see through mesh. You can make the cup eyes by painting the inside of two solo cups black. There are two holes in the bottom of each cup to fit electrical wires through. I soldered three leds in series two a battery pack with an on/off switch to make the lights for each cup. I used a box from the bottom of a water bottle bulk package to keep my head from touching the cups, but I've read that you can attach a helmet to the top of the inside of the box with some cardboard filler if the box is large enough to fit the cups and the helmet. I also made shoulder straps (which really hurt my neck) because I didn't have an actual helmet inside to keep the box head on. the last thing I did was take some leftover cardboard and tape to make the bolt ears.
There's also gold foil wrapped around the box. For another version, I put the cups in first, then gold foil over it. It made it look a little more futuristic.
The difference in led brightness between the first and last picture is because the first was after I had soldered it, while the last was a one led circuit that was taped instead of soldered.