Logging in onto your PC doesn't mean relinquishing access to all other users. Collaboration isn't just emails, chats, and overly complicated file-sharing corporate websites. Most cooperation is still happening in the old-fashioned human way, talking to people, sitting by their desk; working together.
Ademas is the first Operating System that emphasyzes human-human interaction, by enabling sharing of files and applications while sitting at the same desk, in full respect of privacy and security.
Logging in doesn't require another user to log out, or to suspend their session making all their applications temporarily unreachable. Ademas allows any number of users to simultaneously log in, making applications installed by any users available to all users. Projects are also shared, using a sophisticated scheme of protection levels that prevents sensitive material from being disclosed, even accidentally.