Why would Evernote want to do this? Simple the ability to index files that I use as part of my premium membership would be greatly enhanced as it would have access to more of my files other than what is current;y uploaded in Evernote directly. For the files I have uploaded including PowerPoint and PDF being able to search across them is the reason I thought of this idea in the first place. As Evernote works to promote it's Business services I would think this feature would become even more important to their success as it's the path of least resistance by allowing it's customers to index files in locations like Dropbox and yes Box and others. The question is, would Evenote users pay a little bit for this feature, I would.