One more free service which can definitely help you to keep your inbox free of spam is the 10 minute mail. You can simply click to get a disposable e-mail, which can be used for forum sign-ups, website subscriptions and lots more! As the maker said:

"By clicking on the link below, you will be given a temporary e-mail address. Any e-mails sent to that address will show up automatically on the web page. You can read them, click on links, and even reply to them. The e-mail address will expire after 10 minutes."

You can also lengthen the time in which your disposable e-mail will self-destruct, so don't sweat to make it in 10 minutes if you can't.
Nice and easy, kudos to the makers!