Event Calendar started as a replacement for an antiquated script to generate meeting invites with attached ical. It has since grown to be a full fledged event calendar system for public events. Important to Event Calendar is the theory of multiple interfaces, where any data in the system should be accessible in a multitude of ways. For events, this means via nice HTML, iCal, XML, and JSON. Event Calendar also includes integration with Google Maps for directions to event locations.
Shapado is a multi-topic and multi-language question-and-answer Web site service à la StackOverFlow where users can vote on questions and answers and receive karma. Unlike StackOverFlow, people can ask questions on various topic by picking a category (science, programming, business, politics, etc.). It is also possible to subscribe to categories or groups of categories.
Noosfero is a Web platform for social networks. Besides the regular social network features (such as friends and communities), Noosfero offers a full-featured CMS, making every user or community profile a complete Web site with several types of content (including text, image gallery, and file uploads), RSS feeds, agenda, the possibility to set custom themes, and other features. It is also possible to run several independent social networks within the same Noosfero installation.