I just got back from Madison, which is mad about Halloween, and then I was emailed this exceedingly cool Halloween costume idea: dress up as a jellyfish with flashing LEDs.
It looks easy: here are the full instructions, with the traditional hot glue gun and soldering iron, but no duct tape, which does violate the rules of home handicrafts, I think. The only drawback is that the LEDs cost about $2.50 each, which adds up. The jellyfish uses 18, but if you modified this to make a luminescent squid, you’d only need 10.
Another virtue for the paranoid parents out there, though, is that the late night traffic won’t be able to miss seeing your kid when he or she is crossing the street.