Bring some walkie-talkies. You can buy them at WalMart for around $35 a pair. They're great for keeping in touch with everyone on the ship and in the ports. Make sure you get the kind that have sub-channels so you aren't bothered with everyone else's chatter.
Also bring a shoe organizer. The kind that hangs over the door. They are great for storing your stuff in the room and keeping the clutter off the vanity top. You can get these at WalMart for about $8.