Surprise Biker Theme 50th Birthday Party

My husband turns 50 in April and I`ve been planning his biker party for months. We`re both avid riders so it was a perfect theme. I`m having it at a hotel and they`re doing all the food and cleanup. I`ve got a friend who DJs on the side and I made the coolest invitations that say "Russ has gone hawg wild and harley crazy" and I`m enclosing with the invitations a temporary tattoo for the guest to add to their biker wear for the party. I`ve also made him a scrapbook of his life and done a poster for everyone to sign. I also made a backdrop that looks like a police lineup and a sign for everyone to hold that has his birthdate on it for the police lineup number. I`m going to take everyone`s picture standing in front of it. Does anyone have any more unique ideas I can add. Any help is much appreciated.