Is there a way to divide an entry's data into multiple subviews with unique URLs?
Disclaimer: I haven't ever used structure, but hopefully the method described below also works for that section type.

You can do this quite easily with URL-segments

Consider a URL like so:

http://www.domain.com/section/entry/

http://www.domain.com/section/entry/subview-1


And so on.

The section/entry route will hit your entry template, but you can create a new route

section/{slug}/*


And point it to your subview template.

There, you ask craft for whatever is in URL segment 3 like so:

craft.request.getSegment(3)


And display content based on that.

To get the entry you are on currently, just filter on segment 2 like so:

{% for entry in craft.entries.section('section').slug(craft.request.getSegment(2)) %}
    {{ entry }}

{% endfor %}