A graphical user interface in which object thumbnails are rendered in a
three-dimensional environment and which exploits spatial memory. The
objects may be moved, continuously, with a two-dimensional input device.
Pop-up title bars may be rendered over active objects. Intelligent help
may be provided to the user, as visual indicators, based on proximity
clustering or based on matching algorithms. The simulated location of the
object thumbnails in a direction orthogonal to the surface is based on
function, such as a linear, polynomial, or exponential function for
example, of one or more object properties, such as number of mouse clicks
since selected, age, size, etc.