I love the light badges that they had for a short while (see my avatar to see what it looks like) or the wands with Mickey's head with leds inside that change to a bunch of different colors rapidly.
Next, I'm not too much a fan of those spinning toys, either, especially when parents don't stop their kids from playing with them when going on attractions. Again, they light up things that aren't supposed to be lit up, and the whirring noise they make is truly obnoxious.
We usually bring our own glow in the dark stuff (way cheap at Dollar Tree), but we've also purchased the flashing necklaces and such. I have an older Mickey Mouse round light up necklace that people always notice, ask where to buy. I have to apologize as it is at least three or four years old, and on its umpteenth replacement battery.
At DL I bought a headband with glow in the dark mickey ears made out of the glow in the dark necklaces. Very cool but I didn't find them in DW last September :0(