I like fakemailgenerator. They have multiple domains, and incoming emails are shown almost immediately (very fast email servers and push notifications). http://www.fakemailgenerator.com/
Trashmail has an API, so good for various scripts.
If I remember correctly you don't have an inbox, you just forward X messages to another email address, where X by default is 2. After that the email is deleted.
If anyone has any experience with any of these and could comment on how they compare to mailinator, that would be very useful.
[1] - http://10minutemail.com/10MinuteMail/index.html
[2] - https://anonbox.net/
[3] - http://anonymouse.org/anonemail.html
[4] - http://trash-mail.com/
[5] - http://www.dispostable.com/
[6] - https://www.silentsender.com/