Since the earliest PARC systems in the 1970s, the design of GUIs has been almost completely dominated by what has come to be called the WIMP (Windows, Icons, Mice, Pointer) model pioneered by the Alto. Considering the immense changes is in computing and display hardware over the ensuing decades, it has proven surprisingly difficult to think beyond the WIMP.

A few attempts have been made. Perhaps the boldest is in VR (virtual reality) interfaces, in which users move around and gesture within immersive graphical 3-D environments. VR has attracted a large research community since the mid-1980s. While the computing power to support these is no longer expensive, the physical display devices still price VR out of general use in 2004. A more fundamental problem, familiar for many years to designers of flight simulators, is the way VR can confuse the human proprioceptive system; VR motion at even moderate speeds can induce dizziness and nausea as the brain tries to reconcile the visual simulation of motion with the inner ear's report of the body's real-world motions.

Jef Raskin's THE project (The Humane Environment) is exploring the “zoom world” model of GUIs, described in [Raskin] that spatializes them without going 3D. In THI the screen becomes a window on a 2-D virtual world where data and programs are organized by spatial locality. Objects in the world can be presented at several levels of detail depending on one's height above the reference plane, and the most besic selection operation is to zoom in and land on them.^[18]

The Lifestreams project at Yale University goes in a completely opposite direction, actually de-spatializing the GUI. The user's documents are presented as a kind of world-line or temporal stream which is organized by modification date and can be filtered in various ways.

All three of these approaches discard conventional filesystems in favor of a context that tries to avoid naming things and using names as the main form of reference. This makes them difficult to match with the filesystems and hierarchical namespaces of Unix's architecture, which seems to be one of its most enduring and effective features. Nevertheless, it is possible that one of these early experiments may yet prove as seminal as Engelbart's 1968 demo of NLS/Augment.