Interesting bridge to the physical world of social networking. Allows you to easily connect with people in RL and have them automatically managed within your online social networks as well. Supports profiles for business/personal etc.
“Synchronize Google Calendar and Apple iCal. Share calendars between multiple Macs. Share calendars with your coworkers, family, and friends. And while you’re at it, connect Google Calendar to your iPhone, iPod, and other devices.”