One thing one can do with a digital camera and some post-processing is to have a character move in the frame; here's one image of France's first lady walking in a public park for example: https://i.imgur.com/sC31sEf.png
What I would love is to have all of this all done in-camera. It would be great for children to get them interested without having all of the boring 'complicated' computer stuff afterward.
Imagine a camera with a three-way switch, mode A, mode B 'normal', and mode C.
Flick a switch to ModeA and then stack multiple exposures until I flick the switch back to normal at which point the camera composites the images into a single photo.
Or Flick the switch to mode C and then take a slices of photos and then arrange them as diptychs, triptychs etc etc. until I flick the switch back to normal at which point the camera composites the images into a single photo.
With screw on camera filters for IR, colour tints etc.
Great product idea. Cameras already have panorama & HDR modes, it's not super far-fetched to imagine selecting an object present on different frames and having the camera compose it, or even having the camera choose the relevant object automatically.
The problem would be to put this in a camera for kids. If I judge by my own, kids are expert at breaking things. So the camera would have to be super strong, and super cheap, so that replacing it when it inevitably breaks isn't too painful.
Or roller skating in front of the Musée d'Orsay: https://i.imgur.com/2kIlWSK.jpg