You enter a movie title, and it picks an even older movie such that your movie's release date is the midpoint. For example:

    Today <-- 22 years --> The Matrix (input) <-- 22 years --> Star Wars (output)

In other words, today "The Matrix" is as old as "Star Wars" was when "The Matrix" came out.

Seems to just highlight relative distances in time. In Back to the Future (85), he went back to a completely different world of 1955. Yet, Back to the Future is further in our past than that jump (yet many will say it doesn't seem that long ago.)