Every year for the last three I've made a costume for my kitty Lilly instead of carving a pumpkin. (Pumpkins are sticky, the guts get everywhere, and they begin rotting as soon as you've created your masterpiece. Kitties are soft, fluffy, and the only mess they make is the occasional hairball.) This year, Lilly's none other than Benedict Cumberbatch's Sherlock! I think she pulls off the haughty disdain rather purrfectly, don't you?
Do you have any photos of your pets in costume? I'd love to see 'em!