FriendFeed had the best social network mechanics of all social networks I ever saw. Part of it made it into Facebook now (but I can't consider really using FB).<p>Unfortunately, it had no monetization strategy. I suspect that if they had optional paid accounts by now (e.g. $3/mo), many people would pay just to keep the thing afloat and their community intact.<p>Unfortunately, there seem to be only two ways for an online service to last: to become paid by users commercially, or to become "paid" by users' labor of love when they install and maintain it. The later practically requires the service to open its source code.