Prior to Windows Vista it was known as Longhorn which was revolutionary Windows Operating system. Microsoft had planned very big with Longhorn unfortunately due to time constrains and other issue they need to drop many features and Longhorn name and end product was Windows Vista.
Those users who havenâ€™t seen Longhorn OS here is Longbar which is an alternative tile-based sidebar for Windows XP/Vista/7. It is based on idea of Longhorn Sidebar. LongBar shows some relevant information to user using tiles.
Tiles are mini-applications which can show some information or perform quick access to programs or actions.
Longbar in Action