It was announced a few months ago, but I only recently found out about Tonika (via wmf's blog): http://5ttt.org/ http://5ttt.org/ It's not directly comparable

It was announced a few months ago, but I only recently found out about Tonika (via wmf's blog): http://5ttt.org/ http://5ttt.org/ It's not directly comparable to Diaspora or GNU Social, but to me it's much more interesting than either: a distributed, secure framework for building an ecosystem of HTTP-based social networking services, rather than simply a free software "clone" of Facebook.