We get, on average 15million emails a day with peaks much higher.

Definitely don't confuse that with ad revenue. No one ever ever said we get millions of users a day. Alexa or Quantcast can show you real user traffic - please consider ad revenue to be more realistically based off those numbers.

Simply emails. Pure spam. Once a user signs you up - you're getting spam for them - forever.

If you think of a dead-simple feature Mailinator doesn't have - its because we've probably tried it and backed it out from abuse.

With no exaggeration, we get one or more subpoena inquiries or subpoenas a month. On top of that, we have more code in anti-abuse systems than features. A sad reality but otherwise we'd be long gone. Despite claims of Mailinator being often banned, we go a long way to prevent people from using a feature like forwarding to automatically do an internet vote thousands of times. While that would be fun, we'd be banned in short order and that helps no one.

The most interesting point to me is that you need very strong infrastructure, servers and bandwidth to handle the load if you become popular. In other words, there are many many Mailinator copycats and historically, once a copycat reaches a certain level of popularity, the owners need to make a decision.

Paying for all that isn't easy. As far as I know - this is exactly what happened to the now defunct disposable email sites Pookmail, 2prong, and dodgeit.

Death by popularity without revenue.