Yahoo has had disposable email for a long time. You can create upto 500 disposable email addresses (by going to Settings->More Settings->Mailboxes).
Also, you can give this email address a base name that is different from your normal email address so if your normal address is xyz@yahoo.com, you can have "abc" as the base name of your disposable addresses, and your disposable emails will have addresses of the form abc-<your-chosen-disposable-id>@yahoo.com (abc-spamsite1@yahoo.com for example).
So unlike gmail's "plus" email addresses, it's not possible to decipher your real email id from the disposable one. Very handy.
Combine this with Firefox's ability to remember userid/passwords and sync across devices, and you have a powerful privacy toolset that is not a pain to use and is not controlled by any single entity.
I create unique email addresses per service. The pain is in autocompleting email inputs in signup forms. It will suggest a bunch of email addresses that I used on other services and not a new one to use for this service.
Also, you can give this email address a base name that is different from your normal email address so if your normal address is xyz@yahoo.com, you can have "abc" as the base name of your disposable addresses, and your disposable emails will have addresses of the form abc-<your-chosen-disposable-id>@yahoo.com (abc-spamsite1@yahoo.com for example).
So unlike gmail's "plus" email addresses, it's not possible to decipher your real email id from the disposable one. Very handy.
Combine this with Firefox's ability to remember userid/passwords and sync across devices, and you have a powerful privacy toolset that is not a pain to use and is not controlled by any single entity.