Want a quick and anonymous email address at no hassle? Send a note to firstname.lastname@example.org. Now go to the Mailinator site and enter the email address fizzbin and you’ll see the email you just sent. No password, no privacy, no problem. Any account name will work. Try it!
Mailinator was invented as a sort of tax dodge. Go to a site that gives you something for free, and it’s very likely that they’ll demand your email address so they can market to you later (that’s the tax). They’ll demand a working address by making you click through the email they send you. Mailinator avoids this problem by displaying (insecurely, by the way) any mail to anyone. And if Mailinator gets spammed as a result, well, that was the whole idea. If you always retrieve your email within an hour or so of receiving it, Mailinator can function as a perfectly reasonable free email service.
It’s hard to outsmart the web.