19. The system of claim 18 wherein said format element includes a color merge element wherein an area on the display screen defined by two overlapping expandable container images displays a color different from the colors unique to the two overlapping expandable container images.
19. The system of claim 18 wherein said format element includes a color merge element wherein an area on the display screen defined by two overlapping expandable container images displays a color different from the colors unique to the two overlapping expandable container images. 20. The system of claim 19 wherein the color in the area on the display screen defined by two overlapping expandable container images has a spectral relationship to each of the colors in the two overlapping expandable container images.