Have the ability to set a slide as a 'return to' slide.
So that for an interactive presentation you don't need to duplicate the same slide multiple times in order to jump to it and then jump back to where you came from.
i.e. in reveal.js I would use:
slidetoreturnto=Reveal.getIndices(); to set the location of the slide to return to and then
Reveal.slide( slidetoreturnto.h,slidetoreturnto.v, slidetoreturnto.f ); to jump to the slide which i have remembered.

This feature would work well when you have a zoom on a slide or an information page with a close box where you want to click the close and it returns you to where you were previously.
As i say at the moment we are doing it by duplicating these slides ,multiple times.