Today, whilst searching for a 'Newsboy' hat to purchase, I found a rather interesting website named Shorpy. A blog style site, filled with a constant stream of updates including images from the past, mainly America late 19th Century up until the 1970's.
What I couldn't believe was the level of detail, cleanliness and overall sharpness of the images, especially the late 19th Century ones, usually you find that images from this period are not well looked after and aren't available online in such high resolution.
So if you are looking for a very detailed window into the past, look no further than Shorpy. I myself have two cameras that were used to take similar images, The Kodak Folding Brownie (I and II), I do plan to respool some 120 film for use with the Brownie (as noted here) to see what the early 20th Century camera's take on the modern world is.
My favourite find so far (below), click image for larger resolution.