There are some groups of which could gain a specific profit by using laptops. For instance blind or visually impaired people (I explicitly avoid to say handicapped people). See Accessibility-HOWTO and Blinux - Linux for blind people for more information. brltty is a program which supports different braille terminals. Festival is a speech synthesis system. Screen and cursor magnifiers are available. See TuxMobil for a small survey of laptop installation reports by or for blind people.