Wow, thank you very much for this!

One criticism, though: there is no clear mention of the service being free (as I think it is, from the login process). Maybe it might be interesting to put this info in the FAQ, and the API limitations for non authenticated / authenticated calls?

Just one more thing: the data from the Brazilian Central Bank is not showing up. When you click the raw data link, it goes to a page that displays an error about an expired session.