No, it's not a pun, it's webpage.
Ever had to create an account to see something on the web, but don't want to give them your real email address? You know if you sign up you will get 20 more spam emails a day (although Gmail puts it all in one place, so that's solved), but you really want an account just to check that one thing.
Mailinator.com is your solution. Think of it like a drop box; you tell people what your address is, and they drop stuff there. Mainlinator allows you to create fake email accounts with no signup, login or anything at all, and you can just check your mail there. Besides the speed of access (you just type in your username, no password needed), the main difference between Mailinator and normal email providers is you can't send mail. In fact, Mailinator was built explicitly for the purpose of using a fake email to get access information.
It has been floating around the web for a while, but today is the first time I thought I should use it.