We thought about this for raygun.io. In the end, despite being a an error notication service at our core, we thought it was a bit of a dick move to try and hold

We thought about this for raygun.io. In the end, despite being a an error notication service at our core, we thought it was a bit of a dick move to try and hold off people who used mailinator. Treat others how you want to be treated: If I wanted to use mailinator to sign up for a service I'd be miffed if they actively blocked it.