Someone set off a bomb close to my house. Police asked me questions about it (time, what it sounded like, etc). They noticed I had security cameras and inquired what I had. The dumbfounded look when I said Ubiquiti (they've never heard of it) and that all footage was recorded locally on a hard drive. Like they didn't understand what that meant - obviously they were looking for an answer such as "google" or "amazon" so they could just circumvent me.

"Net send" message to every windows PC in the school. IT was not happy about that. Guess they should've disabled that exploit. I think it was before windows xp had (SP2?) disabled it by default.

Proton and fastmail you can use custom domains. I only have experience using fastmail. They provide great instructions for the settings in cloudflare (mx records, etc). My domain is purchased through namecheap.

I can receive mail on *@mydomain.com and I can send email from any thing I want ad-hoc (anything@mydomain.com or anything@anything.mydomain.com)

I thought about selfhosting as well, but the internet concensus was it can be a hassle with your email getting rejected.