There are quite a few communities and services built around software (notably extensions and plugins). For example, Firefox
provide skins and extensions; WordPress
has themes and plugins; Drupal
is essentially is built for extensibility; and Eclipse
has just about anything you can build on top of the platform. Extensibility alone is a major factor in the success of many open source projects.
And then there are behemoths like Ubuntu
and Directory Opus
, each of whose communities contribute a large share to their success.
So which software apps/projects have the best supported and most vibrant communities?