More specifically, the GIF contains the activation code in its comments section: http://www.velvetcache.org/2014/08/20/custom-mailbox-betacoins http://www.velv

More specifically, the GIF contains the activation code in its comments section: http://www.velvetcache.org/2014/08/20/custom-mailbox-betacoins http://www.velvetcache.org/2014/08/20/custom-mailbox-betacoi... I don't believe any hardware IDs are used. The codes are one-time use only, and your Dropbox/Mailbox account is activated with it. Once your account is enabled, you can use the beta on multiple computers.