Andres Aguiar sends word that  Joel on Software sends word about Mailinator.

Need a disposable email address so you can sign up for some web site, quick? You've already got one, at Paul Tyma's clever Mailinator. J ust send an email to any address @mailinator.com. Your email address already exists. Get your email sent here, THEN come check mailinator. Your mail will be waiting. More proof that great UI design is done by taking away, not adding things.

[via Joel on Software]