Firefox Relay
I've been using this pattern for years.<p>I have a custom domain just for signups, and I sign up with [service].[username]@customdomain. The domain simply has a catchall email "accounts@customdomain"<p>Combined with a password manager (Bitwarden) this is absolutely brilliant.<p>* Spam: if I get any spam, I know exactly which company is responsible, whether directly, through selling user data or because of breaches. And I can simply block the whole alias.<p>* Multiple accounts:  If you need a second account with some service, you simply use a new alias. No need to worry about secondary emails just for a few accounts.<p>* Mitigate data leaks: if some database gets compromised, all they get is a throwaway email. They also can't try to log in to other accounts or do password resets if they get a hold of the password. (somewhat redundant with a password manager and unique passwords, but still)<p>* Privacy: all those ad data aggregators have a harder time connecting me between accounts. (of course they still use names, address, credit card info, etc; but it helps)<p>* Easy self-hosting: email hosting can be a pain. But in this case you only need to receive, never send. And receiving basically always works, even with the most broken email server setup.<p>A downside is the unique domain name. I always wanted a shared domain with lots of users to further reduce exposure.<p>I actually thought about starting a service that provides this, but it's a niche product with non-trivial technical hurdles and potentially lots of support demands,  so I'm happy that Mozilla is offering this.<p>The only downside is that people get really confused when they have to deal with your email, for example when calling support. But it's never been a real issue.<p>Highly recommended!