The trick is to scare AND confuse at the same time... that will catch everyone's attention!
Followup: Here's a great bike helmet to start your cause!
These are fantastic. If these costumes weren't so much trouble, I would seriously consider one.
I've got a string of small LED Christmas lights that I used to put on my commuter bike during the holidays, but haven't used them in a while. They never seemed to generate much reaction, at least from what I could tell while riding my bike.
This thread is awesome.