In my new 2008 Berlitz Guide to Cruising and Cruise Ships, it has the Magica and Fortuna listed as having ONLY 220 electrical current outlets in the cabins. All other Costa ships are listed as having either only 110 or both 110 and 220. Can anyone confirm that this is accurate? If so, do you recall what type of prongs it takes?
Berlitz is a pretty accurate book, but I would be surprised ifthey don't have 110.
Depending on what you want to use on the ship, the answer may be as simple as a two prong converter.
Laptops, camera and cell-phone chargers are often compatible and can tell how much voltage they are seeing. Just check your device and SEE if it says "voltage 110-220 V." If so, you just need a two-prong converter.
BUT, if you are talking about hair dryers, curling irons and other things that are more "electric" than "electronic" then you CAN'T just plug it in - you could burn your hair off.
I am the editor, but I also speculate, ask questions and play devil's advocate. I reserve the right to change my mind.