Yes, I did that years ago when I was in high-school, but I currently don't mind paying for it. I don't have too much to configure sendmail, procmail, IMAP server, etc.. Maybe I'm getting old. It was definitely fun and a good learning experience..
Why though? There are zero reasons and guarantees that the company hosting it isn't data-mining your emails. It's just like free email, but you pay for it.
With your own server, it costs way less and you control everything.