The code for many of Plone's add-on products is available from the Plone Collective, which is a unique, community-oriented code repository.

If you have developed an add-on product for Plone that you'd like to make available to others, we strongly encourage you to add it to the repository and to list it in the Products section of Plone.org. 

Anyone can check out code from the Collective, and any Collective user can check in code to any product in the Collective.

This open, community-managed code repository makes it possible for Plone developers to contribute to, fix and extend each other's work.   It's a trust-based system, and it's a vital part of the Plone ecosystem.

If you would like to get write access to the Collective, please create an account here on plone.org, then file a ticket in the Plone ticketing system requesting Collective repository access.  In your ticket, please include the following information:

• Indicate that you are requesting access to the Collective repository.  (Plone has several major code repositories, which have varying requirements for access.)
  
• Describe why you want to have commit access - do you have a new project to check in, a fix to contribute, etc.
  
• Select commitaccess as component

More details on Plone code repository access are available at: http://dev.plone.org/plone.org/wiki/SubversionAccess