It is fairly easy to get a group together - the organizer gets a freebie and some other kind of commission for being "tour guide." Depends on ship facilities, but ship theatres are usually free during the daytime. All you'd need was a projector. So go do one.....
Went on a cruise from New York to Bermuda two years ago with the mounties - relatives are members of the force - and had several group activities with them.
You get tired of the shows pretty quick and it was just one week. Took the laptop. A good creative break. Did this artwork in Cinema 4D:
"Peering inside the mind of intrepid Swedish Crash Test Dummy "Sven" after he and his Crash Test Dummy family successfully endured numerous high-speed roll-over crash tests in the dramatic new and extremely safe Volvo XC90 SUV."
Dwight Atkinson