If you want a striking visual experience, visit an Eastern Orthodox church and check out the icons. You can get a good idea what they're like from printed reproductions, but for the full impact you need to encounter them in their natural environment—the domed space of a church interior, surrounded by other icons.
Their eyes seem to gaze back at you. The rich, saturated colors—often including gold leaf—seem to produce an atmosphere that surrounds you. If that weren't enough, most icons employ a technique called reverse perspective that places the vanishing point not in the background of the picture, as it is in realistic illustrations, but in front of it, outside of it—about where you're standing when you look at it. It causes a sensation that the icon is observing you.
These things give icons a sense of reality, even though they're far from realistic in the way we usually mean that term. Those experienced in the veneration of icons call them “windows into heaven”—windows not only for looking into a higher realm, but through which the higher realm looks back at us, with transforming effect.