I have a key for the new Alpha, just released today! I made 2 accounts in order to ensure the clan tag I wanted was safe, so I got 2 codes: because of this I can't guarantee if you will be able to claim your own tag, but it's better than nothing right?
On the email it says go to playhawken.com and make account (if you don't have one) then use this code in the Redeem Code section of the site (top right corner)
First person to reply get's it! EDIT: I have 2!