Stack Overflow has an awesome set of badges that recognizes a persons contribution to the community and allows an individual's capabilities to grow the more he contributes.
What techniques can I use for open-source or coding projects? For example, a person's contribution to the code base earns them badges along with ever-increasing set of capabilities on the project?
Moderator note
Providing a link to a recommendation is not enough: please provide detailed answers about how to incorporate gamification elements into an open-source project. Any answer that doesn't do this will be deleted.
See Good Subjective, Bad Subjective for more information about the types of questions, and the types of answers, we're looking for on Programmers.