To read more, see the product page.

Impressive, isn’t it?  To get it, just go to this promotion page:

Now enter a valid (read: Mailinator-like site) email address and click send.  They’ll send an email (dozens over the course of the year, actually) to the account.  Open the link, and just accept all the default options.

There will be a message on the top that tells you your key has been sent, so go back to the mail account. Now you have your key!  Just download and install the software (from here) and enter the key.