http://www.fastmail.fm - they have a 10 MB account for free.
http://www.x-mail.net - they have a 20 MB account for free and they have a whitelist queue. You just add the GPTR email address to the contacts (e.g. rewards@somegptremail) and then it goes to your inbox automatically.
Remember that some programs don't accept mail.com, hotmail.com cause of bouncing mails or the fact that the emails could be blocked as spam.