http://www.butterscotch.com/show/Avoid-Spam-With-A-Disposable-Email-Address
From the page: “Stacy Reed explains how to use GuerrillaMail, a site that provides its visitors with
disposable email addresses that expire within an hour’s time. This service is ideal for situations where you need to sign up for a service you only plan to use once, so you can avoid the subsequent spam as well as the headache of having to unsubscribe later.”