[PaulHoule]

I think the problem can be made more tractable by taking the square root of it and building a search/browsing interface over existing apps.

[methochris]

meh, i would never invest in building a business on the back of a company that could ruin me by disabling one little API key

[PaulHoule]

OneNote exports data in files with a defined format, so they can't ruin you that way. For search to be useful, it is going to have to work over email, documents, and everything else anyway. Otherwise you are going to have to search for everything in 15 places whenever you want to look for something.