Resources on Gamification

For K-12+:

More General or Corporate Focused(?):

Other Related/Valuable Resources:

Those resources are by people I know or have met.  There are lots of other selections in Amazon.  Kevin Werbach does a huge and vastly popular Gamification MOOC about once a year.  It looks like some of the resources are still open/available (https://class.coursera.org/gamification-002/lecture).
Gabe Zichermann and Lee Sheldon have some good videos/TEDTalks on YouTube.  Michael Matera and Matt Farber are K-12 Educators and active in Twitter Chats on the topic.