“pptPlex is a plug-in to PowerPoint that explores an alternate method for presenting a slide deck. Using pptPlex, you can present your slides as a tour through a zoomable canvas instead of a series of linear slides.”
I tried it and what I found interesting is that pptPlex allows you to group your slides in sections, then you can move slide after slide, and from one section to another with nice animations.
pptPlex comes with several pre-defined backgrounds for your whole deck:
Download and try it for free: