Mailgun is a fully featured email solution for all your transactional email needs. They offer a nice free plan which allows similar functionality to my service

Mailgun is a fully featured email solution for all your transactional email needs. They offer a nice free plan which allows similar functionality to my service for i think 3 domains. However as soon as you go over that it can get expensive very fast as they offer much more than just receiving emails. Next to that i am not always happy with the transaction speed as well as the privacy policy of them.