Fastmail because it works on ALL of my computers. Hotmail, Gmail, and so on ONLY work on ONE of my computers.
For work I use email on my own hosting, As a public email and for possible spam I use gmail in English internet, on mail.ru in russian.
I generally use my Domain's email. It looks more professional and I can have all my messages sorted automatically by Thunderbird, which works amazingly in Linux.
Google Apps with a custom domain. Have other email accounts forwarded to it. Allows everything to be kept unified in a single place.