It's easy - just select the desired access level, copy this link and send it via email, instant message, etc.Link: Just a link to your wiki. Post this anywhere and people can ask you for the invite key.
Pownce PHP API ClassUPDATED This class now handles support for OAuth with PHP and Pownce's API 2.0, also updated are the methods of the pownce class, ie. $pownceAPI->sendMessage()
Pownce JavaScript Basic API lib This lib is used to access public data endpoints and provide them on the user's page without the need of a backend proxy. It also includes some widgets. demo
PHP Class for Pownce API 2.0 A very easy to use PHP Class that covers all API calls & their options for the Pownce 2.0 API. Link includes screencast of how to implement also.