FastMail

 FastMail  is a popular independent web-based paid email service (launched in 1999) that focuses on privacy, used by some folks in the IndieWeb community with their personal domain.

How to migrate from Gmail

 * https://www.fastmail.com/gmail-alternative

Spam detection

 * Spam detection (apparently provided by SpamAssassin) is not up to Gmail standards. I didn't get spam for months at a time on Gmail, receive it daily on Fastmail. Despite obvious similarities between the messages and diligently clicking "Report Spam" Kylewm.com [[File:fastmail-spam-problem-2015-04-10.png]]
 * 2020-02-23 My experience is different; spam is no more of a problem than elsewhere, possibly less so.

History
Fastmail was acquired by Opera in 2010, then spun back out in 2013, when the original developers bought the service back from Opera.