Combine this with eye tracking for a page of text that grows just the words or figures you're looking at. You could display a larger page on a smaller one. E.g. show a multi page newspaper section on a single page, illegibly small until you focus on a particular headline. As you focus on that its teaser becomes visible, then the leading paragraph, etc.

You could display a link that when you look at it, it grows and resolves into its own content, recursively. Surf links by zooming in. The back button zooms out. It could be a natural way to navigate a graph of text.