We have a lot of products with the very same picture, we are currently manually editing the database so the server does not send the same image repeatedly. This means a much faster page loading speed if you have for example 10 products with the same picture in a category view.
We would welcome a feature to be able to add an already existing other product's picture to a product.
(or perhaps nopcommerce could do this automatically with an image hashing/fingerprinting algorythm that would find the same images in the database, this would be great)