To be able to open images that are inserted on the page in a popup/modal window or in a FancyBox/Lightbox.
Also, to have varius types of galleries, sliders and slideshows for the images.
this one is very nice : https://github.com/francoischalifour/medium-zoom
It would be very nice just to have a filmstrip like gallery where images open up in a popup/modal as mentioned. Would be super nice for showing workflows with lots of images.