All through my 20s I wore the same costume every time I needed to dress up for Halloween:
My aunt's old 70s style prom dress, rhinestone tiara, artificial-flower corsage, and an artificial roses bouquet, with fake blood drizzled down over my hair, face, bare shoulders, dress, and flowers. Carrie.
It was easy and it always went over well. I'm not really the type to do the same thing twice, but it was easy to pack away until the next year and I was too cheap to invest in more materials to make something new.
I wonder where that dress is now?