Mail~Trail is email compliance and search for your web-application. Sendgrid and others only allow you to each back a short period of time, but if you have a compliance requirement or need to confirm that an email was sent you are out of luck. We have been using this internally for a few months, but just launched for public use and feedback. Our goal is to see if other folks can use this service for their own use or if we are the only ones we found this to be a problem. Please sign up, it's free for now and let me know your thoughts.
https://www.mailtrailapp.com