Theoretical situation. You have to sign up for some random site because you need something. They’re going to send you an email to verify your address, but you’re certain you’ll never, ever use this service again, and the site looks shady. Looks like spam. What do you do?
Fortunately there are plenty of disposable email systems out there for exactly this situation. Mailinator is one of them! You go to the site, you type in whatever name you want, and you can start giving away <name>@mailinator.com email addresses all day long. You can check it once (ANYONE can, so make sure nothing sensitive goes there), click your link, and ignore it forevermore. And if email addresses @mailinator.com are blocked, they have several other domains you can use. I usually have the best success with @sogetthis.com, though for the first time I saw it blocked a couple days ago.
This sort of thing has come in immensely handy to me over the years. There are other options as well, but Mailinator in particular has been quick and easy to use for me.