Does anyone know of a tool like this that can generate reports on a non-gmail service? I would love to see these stats on my work email, but it is run through exchange not gmail.
Sanebox.com offer visualizations of your email, broken out by useful vs time wasting. It's a side effect of them managing your inbox. They'd probably be open to additional data viz ideas
Possibly http://context.io/ though I can't tell if they only support Gmail or not from their site.
Shouldn't be hard to get this working on maildir/nmh mailbox directories, which would be super-useful.