I guess I am a freak when it comes to technology. I carry an iPhone (set to airplane mode) my MacBook Pro (photography computer) and a iPad on a cruise.
I do like Paul and buy the biggest internet package out there. I restrict myself to XX minutes a day to spread out the package so I will not use it too much.
I like having the option to look up info on the fly, stay in touch via email or Skype (depends on speed and the cruise line) and having a way to watch movies, read books or play games (I have kids to keep entertained as well).
The MacBook Pro is used mainly for downloading my pics, editing them and backing them up. Nice to be able to tweak the photos just right!
I use the iPad to play movies on as well as games. It is also a great way to share your pics with others on the cruise. If you take a tour with a long ride back to the ship, it sure is nice to use the camera connection kit and look at your photos on a large screen on your ride back.
The iPhone... never leaves my side
If you like to stay in touch then take along a laptop with you. If you don't like computers then leave it at home and don't rag us technology addicts about it