Every academic author knows the pain of getting the image permissions for their articles, books and other publications. It takes a huge amount of time, money and frustration. However, many institutions will allow free reproduction of images of their collections for academic publications if they fulfil certain criteria, depending on the institution.
This site lists those generous institutions providing open access to images in various ways, and their conditions. Please drop an email if you know of more to add or contact me on Twitter @FourRedShoes.