I am quite discrete in my clothing, black, dark grey, dark green... I need at least 3 XL, but when playing Empire I often wear a Disco-Vader that is quite unnerving and a kick to "purists".
The sister of one fellow player gave us pink T-Shirts with C3 PO drinking a cup of tea while in the background ships engaged, lasers raging. I will never, NEVER, wear it.