I just had a random thought; what if you append "[closed]" to the end of a question title. Is it filtered out, or in some way disallowed?
If you are seeing this, it isn't. It could potentially be used for some trickery, right? Or maybe not. I don't know, that's why you're here: discuss!
EDIT: Just a recap: Juan Manuel edited and removed "[closed]" from the end of the title and then answered (see below) - but it is technically possible.
Edit 2: Looks like it's still possible, if you play silly tricks with Unicode. (There's a zero width non-joiner character in the new title.)