@HerraBRE As much as the movement towards SaaS has done a lot of harm to the internet, I think that "personal SaaS" solutions can help undo some of that.
Mailpile, like a lot of FOSS SaaS-like stuff I've seen, seems to me a like a really interesting (albeit slow) turning point in computing.
Why *not* host a bunch of your own services for yourself, your family or your friends? All the features/flexibility without giving up the control or trusting a company that needs to monetize you.