There are some other projects in which I have collaborated (or at least I tried to), but I haven't been collaborating for a while:

• Apache Jakarta Commons Configuration: Library for Java developer which offers advanced features for reading properties files or access XML files as if it where properties files. I've sent several patches which have been kindly accepted.
• GNOME Hispano (Spanish): Group of people dedicated to promoting GNOME within the spanish speaking community. I was the webmaster and helped convert from a static website to a dynamic website based on XML + XSLT.

I started the project as part of the PhD Thesis at the Universidad Politecnica de Madrid. My aim was to provide a centralized place to document and discuss about the best way to run development projects on a collaborative ways. The first and best examples of collaborative development models are in the free software world although I believe that they can be applied elsewhere as long as the sharing ideals also exist.

• Blog: http://collaborativedevelopment.blogspot.com/
• Wiki http://www.jorgeferrer.com/collaborativedevelopment
  

APICE is an spanish association, sited in Madrid, which works to include children in risk of social exclusion. They use computing classes as a means to teach both social subjects and technology that will be useful for them in the future. I'd like to highlight that they have recently renewed its software infrastructure to use only free software. Each computer used by the children is equiped with GNU/Linux.

My main collaboration with APICE is the development and mantainance of the website, which is based on Drupal.

• Home page: http://www.asociacionapice.org (Spanish)