Quandl is pretty good (https://www.quandl.com/ https://www.quandl.com/). It is a unique API (and has a web interface as well) to a collection of financial and e

Quandl is pretty good (https://www.quandl.com/ https://www.quandl.com/). It is a unique API (and has a web interface as well) to a collection of financial and economics data sets.