Laptops are small, wireless, resource-minimal and portable. Even without portability, laptops have many advantages over desktop machines. Laptops also have their shortcomings, the most obvious of which is price. Laptops are very expensive and difficult to repair or upgrade, although it can be done. They also offer inferior performance compared to desktop machines, specifically in disk access, processor speed and hardware support.
Processors are also slower and more expensive.
Also, laptop processors are physically different from standard processors because they must be small and low-profile, although smaller chips require less voltage so they don't generate as much heat. At the time of this writing, the two Linux-specific laptop providers are LinuxLaptops and ASL Workstations. LinuxLaptops is a specialty shop run by Nathan Myers, which deals exclusively in laptops for Linux and has three models at the moment. It is highly focused on optimization and tuning, working within the interesting limitations of laptop hardware, to maximize Linux performance. Penguin Computing is also developing a laptop, but it is still in beta and was not available for review.