For Halloween (and a Video Games Live concert that was on the 29th of Oct) I made a Liara T'Soni costume. It was quite the experience - I had never worked with latex before so making the headpiece was a new challenge. I think it turned out alright!
I was going to post the comic-tutorial of how I made it on DA, but that will just take faaaar too long to upload. You can read it here.
(it's the Blue Girl Comic)