dexternemrod

@cheprofumo

@MicrowavedTea

You could completely host it yourself (like running all the software) and use a spamfilter.
Not sure how @Tutanota handles spam on custom domains or use the domain via #addyio that's how I do it and it rocks (for me).

@chappedafloat
So you did not take it as a friendly feedback.

@chappedafloat

Just two remarks, some of jour points read like they are based on your assumptions. It's strange to write about 'Linux' because Linux is like an ecosystem of distros, which also are the core of qubesOS.

Please take this as a friendly feedback.