@ jvmacross: Great collection and thanks for sharing your Misa. That is something truly amazing. It might be a real hanken or it might be a very well done fan made version but it is hard to tell just from one picture. One strong indication this might be a well made fan hanken is the lack of the pearls. There really is no reason for the pearls to be missing for a hanken especially, since if it was a second layer or third cel layer, it would block the hair strands and the shadowing around the neckline would be mismatched.
Typically for hankens there is no reason to add a second cel layer if the details can and added to the first. Second layers serve specific purposes, showing details that are either animated (not applicable for hankens) or display extremely unique details. Then these details usually appear above (not beneath) the primary cel layer. Best case scenario this is an original hanken, but if so, you are missing an in-between layer for the pearls, and the separate layer(s) for the tiara and the veil. The tracelines still look amazing solid which is not unusual considering the quality for hankens is higher than production cels.
One questions can you let us know how many layers appear?
Nevertheless it is a good find, but authenticating it might be a good thing to do. Also you might want to re-do your matting b/c it blocks parts of the dress, hair, and shadowing.
Oh and just to add something to Totoro242 comments, hankens are indeed used for promotional publications such as posters. However hankens also are used as magazine cover art, poster splash pages, cd/dvd cover art, and insert cover art.