I think ACEN's hall cosplay awards are a glass trophy with the year and award title on it. The masquerade has actual prizes for the top slots, and I guess the trophies.
Hall cosplay is nice because you can just drop by during the con for judging. The Masquerade usually fills up early (there's a prereg for it) and you need to know what costume you are entering ahead of time.
(I know you weren't asking about the Masq but it helps to know a little about it so you can tell if someone is talking about the Masquerade or hall judging. It can get a little confusing.)