Color and shape (outline, at least) differentiation making it easy to identify icons in one's peripheral vision is a really nice property for icons, and BeOS is

Color and shape (outline, at least) differentiation making it easy to identify icons in one's peripheral vision is a really nice property for icons, and BeOS is pretty good on those fronts. The main sin of the "photoreal" icon set a couple posts up was that it leaned too heavily on two colors (black and silvery-grey), not that it was photoreal.