An author wouldn’t need much of power and storage. A decent surface tablet computer or basic laptop would be fine for their needs. A SD would be perfect for faster documents to load when getting that spurt to Jot down what is in their head before they lose it. And a surface tablet would execute their means of travel and give them the ability to really write anywhere they please. As well a nice decent sized laptop, but I believe the surface tablet would be much more variable.
Video game developers would need a power house computer. With as much rendering and graphical components they use, they would need something with power, storage, and a high end video card. Generally someone as a video game deep. Would most likely have to order a custom computer with the latest and greatest processor and video card. And most definitely a SD/TAB Hybrid for faster loading time. In most cases from what I have seen they are usually grounded with a desktop.
But there are valuable laptops out there that could provide the necessary tool for the traveling designer. CAD users demand a lot of space and power for their machines of choice. With the size of files they create and the amounts of scenes that need to be rendered per save or finished project can be extremely stressful on a lacking computer. A computer with a Terabyte or more, following It up with a high end processor and video card, and fast expandable memory would make the perfect work station.