Rio de Janeiro has one of the most beautiful libraries in the world, the Biblioteca Nacional- www.bn.br
It is considered by UNESCO one of the tenth libraries in the world and the biggest in South America. Part of it is digitized and available on line for research. You will find books, photos and newspapers from many states of Brazil. It’s precious for us doing genealogy.
What I most use is the newspaper database that is available on the following link and it’s fully researchable.
What I like most is that we can also save the images that are significant for our research. I already found some nice references from the XIX century and some of my family members.
I wish the web site were both in Portuguese and English.