Tempinbox – Free Temporary Email Service

There needs to be some guarantee of the longevity of the service's domain name, since someone could claim the domain as their own when you mistakenly refuse to renew it in advance.

The bad actor sets up a catchall, and then would do password resets for all the accounts registered with that domain name. That's why I treat these email relay/proxy services cautiously as if the domain will change hands sometime in the near future.