There's no question that deciding on a cute-but-not-cliche-but-also-creative Halloween ensemble can be a pretty tough call. But there are some couple costume ideas out there that are just plain wrong and should be avoided at all costs (no, seriously).
DIY Halloween: Film Noir Grayscale Costume. Clare Hwæt Wilson: "They missed a very important part of any gray/blue skin character-- tooth color. They need to be WHITE or they look extra yellow. (I learned this from Farscape.)