My costumes are usually like June Cleaver.. or one year I was as a vampire (this was before they were so *cool*) and had a sign that I was a Democrat wanting more of your blood.
We don't decorate, but we're usually at my sisters and she does a lot.. I do have some fun jewelry I wear.. I do fabric flowers.. and I've done a couple in black and white with spider webs.. you can't really tell what they are.. so that makes it fun.