Here is a report on some promising open sorce social platforms available today. Not all developers know these projects this is a heads up to them and anyone who wants to start a social network.
It seems that every hour, a new Pligg-based site is born. Pligg is a PHP/MySQL system that allows visitors to submit websites and blogs for voting or ranking. While very similar to Digg, it does offer some additional features, such as trackback support, automatic title discovery, and RSS import functionality. It also has a small community that is actively working on new mods and templates. Some of the more interesting Pligg-based sites are PlugIM, Sk*rt, Sphinn and Simply Fired.
NewsCloud is another content management system that has a story ranking feature. They have also developed a Facebook app for their service, which is open source as well and available for download. The default layout is slightly more newsy than Digg-like.
Most know Drupal as one of the more popular open source content management systems available. Thanks to the user community, several modules have been developed that allow voting of submitted stories. Recruiting.com uses this setup.
Dolphin, from Boonex, is a popular free community-building application that is being used for a number of dating sites. Many modifications have been developed, however many of them are only available for a fee. There is also a cost associated with removing the company’s links from your site.
PHPizabi is another social networking script that charges a fee to remove their branding. They are rapidly approaching 100,000 downloads of their software, and have a few impressive-looking demo sites listed on their website.
Elgg was developed with the educational industry in mind, but can be customized for any use. Many universities throughout the world have adapted the social software to fit their needs.
Developed by Red Hat, Mugshot allows you to post what you are reading and listening too, and share it with you friends. Mugshot is a little different, as both the client and server code are open source and available for download.
AroundMe is an open source social networking app that supports OpenID. They are based in Sweden. We haven’t seen many sites running on the platform.
GetBoo allows you to save you favorite sites and share them with your friends. It also supports public and private group creation.
While Scuttle has not been updated in over a year, the code is still available on SourceForge. Scuttle is a PHP/MySQL-based social bookmark system.
More suggestions? Add them in the comments.