Fastmail can generate random@fastmail.com email addresses that go straight to your mailbox. Really useful for throaway accounts and low value services. It apparently has an integration with 1password but I can't vouch for it as I haven't used it.
1password integration is nice, because you don't have to open up Fastmail to generate a new masked email.
I just use catch-all with custom domain, though. That way, I'm not tied to a particular provider, and I can make new "masked emails" on the fly however I want (usually, just using the name of the app/website I'm signing up for). The downside is that you loose the previously mentioned anonymity since a hacker could link your various addresses by domain name. But it's still way better than using the same email address everywhere!
It wont forward to your inbox though and is only suited for temporary usage.