Last Halloween I made myself a Marie Antoinette costume. I was pleased with myself, since I did not use a pattern, but instead drafted my own pieces out of muslin. I made it out of cotton, rather than a shiny fabric, because I was poor. However, it turned out really well. I think if I had powdered my hair white, more people would have gotten the idea. I ran out of time, so the buttonholes are just slits I cut in the back. I did just learn a few months ago that the alternations lady at the dry cleaner's will do buttonholes for only a few dollars each. I don't think I will ever learn how to if its that cheap!
I also made my boyfriend a pilgrim costume. That mainly consisted of adding a collar and cuffs to thrift store clothes, but it looked hilarious.
Finally, I made my wiener dog a Chiquita banana costume. He was sooo cute. I made it out of felt, so it was easy to sew, pretty sturdy and cheap. It turned out beautifully, although the dog did not enjoy being fitted for his costume.