How To: LED Throwies

Source

I may have a slight addiction to dance movies. Watching Step Up 3 a while back I encountered what the film calls "neoflies" but which are LED throwies. It's basically a form of light graffiti in a way. Create, and attach to any metal surface and you're on your way. They are fairly inexpensive  and just amusing to have around.

Things you'll need:

10 mm diffused LED lights (about 10 cents each at the hardware store)
Lithium battery (mine we're 4 for a dollar I believe but I recently found them on ebay 100 for $20, the more you get the cheaper they are)
Rare Earth Magnet (25 for $15 but this was just what I had on hand, you can use any kind of small magnet)
Tape (any kind, I used electric tape)
or Epoxy (if you're planning on leaving them out, more weather resistant)

From here it's quite simple.
(1) Take the led light figure out which end is the long one and which is the short one; long is the anode (+), short is the cathode (-). Attach the positive part of the LED to the positive part of the battery. If it doesnt light up you've aligned it wrong, just flip the battery and you should be fine. If you're still having problems you've either got a bad LED or the wrong battery.
(2) Hold the battery onto the one side.
(3) Tape it neatly. It looks cooler when it doesn't look like its wrapped in a quarter yard of tape. NOTE: if you're using Epoxy please follow safety directions.
(4) Throw and enjoy.

Cheers,

N. Riazi