I have to take exception to your opposition to rocks. We always keep a few rocks in our candy bowl specifically to give to trick-or-treaters with no costume. Halloween is an exchange: in return for our candy, they're supposed to provide some visual entertainment, however lame.

I'm not talking about crappy costumes like the ones you mention. I'm talking about high school kids who are too old for dressing up and who were just hanging with their friends and decided, what the heck, let's get some free candy. If you ASK them about it, they'll make up something about being dressed as a street punk or whatever. So I don't do that; I form my own judgment. But refusing to give them something just leads at best to an argument, and at worst to your car getting egged. Thus the rocks.

Some years we've gone to the trouble of writing little notes saying "No costume, no candy" and wrapping them around the rocks.

I'd be wary of giving those kids anything they could throw right back at me or any of my windows. I'd rather give them cough drops in non-descript wrappers, marshmallow peanuts, or those awful peanut-butter/chocolate things in the orange and black wrappers.

Those orange and black wrapper things are so gross. I think if you gave me those, I'd just go look for a rock to throw through your window anyway, lol.

Also, Zach, I think it's possible ot be any of the things you have on your list and be so creatively. While I concur that it's perfectly possible to be a boring witch or pirate, as you point out it's also wholly possible to try and be something "different" and totally mess it up. As such, I don't see anything wrong with having a creatively-made "normal" costume.

I suppose this may be a subset of "costumes into which you put the least effort possible," but I'd like to add to the list costumes that chiefly consist of wearing animal ears.

The goal in giving a rock, btw, is for them not to realize they got a rock until they open their bags at the end of the evening (otherwise you are certainly risking revenge). I drop the rock in their bags the same way I drop everybody else's candy in; they're about the same size and weight (i.e. not really big enough to break a window).