The first difference of using the computer on the boat involves power. My preference is for desktops, but desktops, with their hungry power supplies, suck down the juice and as we travel, there won't be lots of juice to suck. A computer designed to operate away from AC power for extended periods of time is required, and that is a laptop.
The second difference of using a computer on the boat involves space. There isn't some large desk space that I can devote to the machine. When the computer isn't being used, it needs to be put away so the activity space can be freed for something, or someone, else.
The third difference involves multi-use. Items on the boat that can do multiple things are more useful than single purpose items. In the case of the next computer, for example, it will have to serve as a media station. If we want to watch a movie, it it will have to be played on this machine. The capability of playing BD (Blu-ray) movies, DVDs, and having an HD display is required. Another set of usages for this machine involve data collection of our journey. Specifically, allowing the computer to tie into GPS instruments to track our progress around the world.
The search has begun. A laptop this go around for my machine. It will need a large screen, have lots of memory, many ports for connecting devices, be HD, have a large harddrive, decent battery life, and pleasure my inner geekness. Given the latest rounds of processors, it looks like it will be an Intel i7. We shall see!