This brings back my favorite Halloween memory ever: The Pair 'o Dice episode that's so funny to me today (and come to think of it, it was funny to me then too...)
In one of my best costume ideas yet, I decided my sister and I would go as dice. It was low-budget and easy, we painted cardboard boxes white and put big black dots on them. Being the math geek I was, I found an actual dice and copied the dot patterns and used a circle pattern to make my spots. My sister's a total dork so she just took a big magic marker and drew circle-like shapes on her outsides; I made fun of her a lot which was mean because she was only like 6, but that's okay.
So anyway, we go trick-or-treating and our costumes are a huge success, everybody thinks we're cute and creative and gives us candy until our trek is cut short by a horrific accident - my sister slips on a driveway (one of those really steep ones) and because she's encased in cardboard slides all the way out into the street with no control whatsoever, breaking land-speed records for costume transportation and landing in a pile of self with candy flying everywhere. A nice effect! She wasn't hurt, but was kinda scaryed and after picking up her candy she didn't feel much like trick-or-treating any more. I of course thought it was really funny, which again was mean because she was only like 6.
When I think of it, my sister always seems okay with going along with my ideas, maybe it's a plague of the second-born or something. I usually pick the Christmas presents for Mom and Dad, where we go out to lunch on any given day, whether it was a Barbie or Lego day when we were little kids, all that. And costumes, of course.
Okay, well, everybody go get scary!