Some of mine from years past:
I wore a negligée with a sign around my neck (read Freudian). As a Freudian slip.
Another 'sign' costume was "Honey? Does this make me look fat?" (Won a couples contest for scariest costume. Really requires husbands. Single guys don't get it)
Furry costume. LOTS of pushed up cleavage in cutout neckline, and big blonde wig = Dahli Lama (Dolly Parton on top, llama bottom). Great for cold climates.
Silver Sequin dress + red ribbon & heels+ sharpie drawn 'tattoos' = etch-a-sketch
CHEATER costume : Sweats & sneakers = "Comfortable"
I went as Braille, once, for a non-Halloween party. Also kind of a cheat.. Because if you can see the dots, you don't get to touch them
Couples Costume = 1 straight jacket, 2 people (one arm each). We're a committed relationship.