From all the examples I listed above, I feel like our spacial sense does not limit to eyes, or visual images, but auditory sense also contributes to it. That means, in order to create a real "stereo" experience of ascending or descending(climbing or falling), we have to manipulate how the perceives' ears perceive from our product. Now, Shepard Tone provide me a brilliant way into these kind of experience-creating. 

Not limiting to climbing and falling, sometimes people need to feel the presence of adrenaline to find something exciting. But how to make our perceivers hot blooded? Shepard Tone could be out way in- the everlasting ascending effect can be used to create the sense of a war or an epic fight is at the edge of breaking or something really exciting is going to break out and shock the perceivers' heart greatly. Shepard Tone could provide a great pre-war environment that help the perceivers to better prepared for getting their blood boiling.