This site is quite specialised but if you're doing research or looking for resources on archaeology in prehistoric, ancient or medieval Britain then this is the place for you. Lots of neat images - they have a link to their photostream on flickr.
This photostream from flickr is maintained by Wessex Archaeology in Britain. It contains images of their excavations and the artefacts they've recovered. Useful for investigations of pre-modern Britain, I would imagine.
The British School at Rome Archive (BSR) thanks to the Getty Foundation, made freely available digital copies of the John Bryan Ward-Perkins photographic collection. A website of the "BSR digital collections was created to present not only the photographic material (Photographs) but also other types of resources which follow into different categories: Maps, Prints, Documents, Postcards, Drawings, Paintings and Manuscripts".
But "the majority of the digital images displayed on the website are represented by the photographic prints and negatives from unique historic collections, including calotypes, glass and film negatives, slides and lantern slides."
Seems to focus more on the history of the British School at Rome rather than Roman history. Should revise the tags at this point but this summer heat here in Queensland is making me lazy...