I just saw this on twitter, and you have to “pay with a tweet” or “facebook post” to get it. Been looking through it and there’s some really good stuff in here. It’s also released under Creative Commons Attribution 3.0 Unported (CC BY 3.0) license (http://creativecommons.org/licenses/by/3.0/deed.en_US)
http://scoreoid.net/community-promotion/
Check it out!