Tip #4: Plus sign in mail addresses (subaddressing)
Some email providers allow sub addressing / plus addressing. Using a + and an arbitrary text (tag) before the @ sign, creates a disposable ad-hoc email address.
This works at least with gmail and live/outlook. Instead of using your regular email address, let’s say firstname.lastname@live.com, you would use firstname.lastname+SomeTag@live.com.
This is specifically useful to send yourself notes, apply rules to in your mailbox when signing up for newsletters, or find out who is leaking your account firstname.lastname+ShadyWebsite@live.com. Later partially works, as this trick is widely known.1
Some services require you to unsubscribe or delete the account sending an email that you signed up with. You only receive mails plus addressed.
Do you know any other providers that allow that? Let me know in the comments.
Some webforms do not allow the plus character. ↩