SocialEngine gives you a simple, unbranded network that you can customize in any way. You’ll have the freedom to maintain fine-grained control over all aspects of your site and content.
SocialEngine helps you build a community that's unique to you, with absolutely no "powered by" links or "SocialEngine" branding presented to your members.
Your community's content is yours to own. Unlike most hosted services, SocialEngine never prevents you from moving your community or serving your own advertisements.
You'll have the complete PHP source code to play with, making it possible to add or integrate your custom features.