What's a good gift for someone who works on a cruise ship?

My brother, a musician, (mid-twenties) has been working on cruise ships for over a year now. He's currently enjoying the lifestyle and will be doing it for the foreseeable future but for events like birthdays and Christmas I have no idea what to gift him. I don't want to burden him with "stuff". if any long term cruise ship employees have advice on gizmos or gadgets they like to have with them or something they like to come home to, I'd appreciate ideas.