same functionality as Google Docs, but locally hosted:

• Feng Office Collaboration Platform
  (formerly known as OpenGoo)
  → http://www.fengoffice.com/web/products.php
• http://www.zoho.com/
• http://owl.anytimecomm.com/

• http://www.google.com/apps/
• http://gears.google.com/

• http://gs.fhtino.it/gdocbackup
• http://ardoino.com/php-google-backup/

• http://code.google.com/p/zkspreadsheet/
• List_of_project_management_software