Laconica (pronounced "luh-KAWN-ih-kuh") is a Free and Open Source microblogging platform. It helps people in a community, company or group to exchange short (140 character) messages over the Web. Users can choose which people to "follow" and receive only their friends' or colleagues' status messages. It provides a similar service to sites like Twitter, Jaiku, and Plurk.
DiSo (dee • soh) is an initiative to facilitate the creation of open, non-proprietary and interoperable building blocks for the decentralized social web.
Using XMind/XMind Pro with XMind.net's sharing service is a revolutionary way to enable both team brainstorming and personal mind mapping. With this major upgrade, we bring Web 2.0 concepts on community sharing into a popular desktop application. Our new Gantt chart view is a must for both junior and senior project managers. You'll find many more pleasant surprises with the new XMind product family.
Elgg is a robust open source social application engine. Elgg provides elegant, flexible and scalable solutions for organisations, groups and individuals. Take advantage of powerful social technology today.