The only way to do so is probably to use video... but I don't think I've seen such effects like this!

Ok. All you need is to create a forward motion ( using a video camera ) and then when the visitor presses forward of any such button, what will happen is that the movie clip is triggered and will play and stop after a number of frames. The backward motion of course is essentially the same logic. Use a video camera!

When the user presses the backward button, Actionscript will have to 'rewind', though I don't know how that can be done...

Don't know why you want to create such an effect though! I've never seen such a thing on any website.