tubri.com is a new kind of social network based on the idea of living in groups.
What problem it solves:
In other networks, the user has to keep all his friends, co-workers, known people, family in one place only and they call it "Friends". (Facebook)
1. Not everyone is a friend
2. User's status updates are visible to all in his network which leads to embarrassments and privacy issues
2. Sending different social updates to different types of people is very hard
3. All incoming status messages of everyone in user's network are placed in just one list
How it works:
1. You organize your people in different personal groups you create.
2. Keeping someone in a "friends" group indicates to tubri that he/she is a friend of yours.
3. Whatever you post in a group is visible to the members of that group ONLY.
4. You can post different things in different groups easily.
5. No one gets to know which groups you have - its totally personal
6. No need to send any group join invitations
Here is a short video explaining all this: http://www.youtube.com/watch?v=uVg3lN8UHcA