I'm new to the world of quant finance, but I'm bringing some experience in data analysis with me. I'm looking for some BIG data sources to start some personal quant research projects. Does anybody know where I can get data arrays for historical equity, bond, and commodity prices? The more granular the data, the better - daily open, close, and intraday high/low would be ideal. Additionally, valuation metrics (at least quarterly) for the equities would be handy. Would like to have data going back as far as possible.