I've summarized 8 pages of this thread.
Email providers sorted by order of appearance, I've only included those people seemed to use themselves (personal recommendations or vouches). Some links to particularly interesting contributions
2022: Added a new and notes
PS: I think this last forum message is targeted spam, but the links here don't count for search engines so whatever.
Update 2022: Corrected formatting etc.
Update2 2022: Added an untested list of ukrainian/russian email providers