Abstract: A virtual computer monitor is described which enables instantaneous and intuitive visual access to large amounts of visual data by providing the user with a large display projected virtually in front of the user. The user wears a head-mounted display or holds a portable display containing a head-tracker or other motion tracker, which together allow the user to position an instantaneous viewport provided by the display at any position within the large virtual display by turning to look in the desired direction. The instantaneous viewport further includes a mouse pointer, which may be positioned by turning the user's head or moving the portable display, and which may be further positioned using a mouse or analogous control device. A particular advantage of the virtual computer monitor is intuitive access to enlarged computer output for visually-impaired individuals.