One of the new changes to InDesign CC is an innocuous checkbox at the bottom of the Table of Contents dialog box for: Make text anchor in source paragraph.
What this does is make sure that any TOC has functional links in the exported ePUB. As Ron Bilodeau commented, “You can now have multiple ID-generated TOCs within your document(s) and they will all exist with correct links within your exported ePub file.”
Now you can have custom contents lists in an ePUB
It would be easy to link to all the captions of the illustrations, for example to get a Table of Illustrations. You could link to titles of tables, or anything else you can think of. Put them where they are needed in the ePUB and when you export it, the links will work.
It’s one of those little things that the InDesign team delights in adding to their software.