So email makes the list. To be fair to author I am in the analysis business and storage or platform beyond baseline criteria are of little interest. My objective is to get information out of data and with email (or other unstructured data) the approach I take is exactly the same as with structured data. I start by drawing the decision trees my customers are going to use to drill into the data. These make it really easy for me to define the 'meta data' or architecture for the data I'm going to warehouse. The final step is coding up the load process which I quite like because I'm working with a two field table. Just in case I've lost anybody here's an example; my users inquiries will be for the most part related to master data; that is to say they will be looking for email with SKU number, shipment, purchase order, contract etc. When I load the data I search for text containing the master data key field and populate results to the index tables. My email is now firmly in the relational space. I understand the "what if" but as long as I monitor search traffic and make sure the vast majority of requests are within my structure I've dodged the pink slip for another day.