This is one of the Free drag and drop scripts from DHTMLGoodies.com.

• Root node
  • Europe
    • Norway
      • Stavanger
      • Bergen
      • Oslo
    • United Kingdom
      • London
      • Manchester
    • Sweden
    • Denmark
    • Germany
      • Berlin
      • Munich
      • Stuttgart
  • Asia
    • Japan
    • China
    • Indonesia
  • Africa
    • Tanzania
    • Kenya
  • America
    • Canada
    • United States
    • Mexico
    • Argentina
  • Cannot have children
  • Cannot be dragged

Use your mouse to drag and drop the nodes. Use the "Save" button to save your changes. The new structure will be sent to the server by use of Ajax(Asynchron XML and Javascript).

Note! I'm not saving the structure in this demo in order to make the script look the same for all visitors