From Drupal and Moodle, right through to a Git versioning system and Perl modules on CPAN, we contribute back to over 175 community open source projects. This list is in order of the number of projects contributed to.
User manageable dashboard UI system
Adds a Document Management System to SilverStripe
Simple on the fly caching of dynamic content for Silverstripe
Exclude children of configurable classes from showing up in the sitetree
Module for improving automatic image cropping in SilverStripe 3
A collection of useful grid field components.
SilverStripe maintenance (https://github.com/FriendsOfSilverStripe/silverstripe-maintenance)
Allows you to watch your SilverStripe application for security releases and updates.
Silverstripe 3 Newsmodule
A decorator for a form field that manages as has_one relation, to allow adding a new object on the fly
An extension that adds a star rating system + UI to any DataObject type