The Cerberus App twitter account just sent out a tweet saying they have reached 100,000 users, and to celebrate, they are giving away licences.
https://twitter.com/#!/cerberusapp/status/173172617774239745
All you have to do is download the cerberus android app, create a cerberus account, and then fill in this form, and you're good to go.
Just an FYI to anyone who is interested.
Disclaimer: I am in no way affiliated with Cerberus App, I just think it's a great app, and thought others might like to know about this promotion. :)