Much has been expounded on social networking. Here are some tools you may want to consider embracing. I'm doing a fast type out here {doing research at the same time for another project} and thought you might need this as ... its as feasible as the next software on the open source neighborhood.

Connotea - a social bookmarking s/w which you can download and install on your server. Similar to Scuttle, its the next best thing you might seriously want to consider for your online community {make it user friendly} for your members, and they'll love you for it!

ELGG - now this one is interesting to even install and play with. Apart from Dolphin {dating community which you can... if you're up to it - modify to your heart's content!} ELGG establishes personal digital identities and connect with other people, collaborate with them and discover new resources through their connections. Plugins allow users on different social networks to collaborate, and provide specific functionality for tasks like project management, mobile browsing and collaboration through user-controlled wikis.

A foundation platform for many social communities, People Aggregator is available for download and installation into your system. Its interesting to note how this s/w does wonders in areas whereby each end-user will control who has access to their personal data, who can use it and how. Each end-user is able to move their data to other systems – whether it be their personal profile record, list of friends, groups, their photos, MP3s, links, bookmarks or events... and more. Interesting stuff for serious developers to consider!