XML - Editor, Tools,...

XML editing software
Java is not compatible with UTF8 with BOM and XOG is based in Java
so use UTF8 (withoutBOM) or cp1252 aka ANSI

--Ms.Notepad XML 2007
(be careful writes UTF8 with BOM)
   Outline view with XML elements. Able to drag and drop elements from one file to other

--XML Spear 3.1. Good free software! it is possible to select the enconding(even UTF8 with BOM)
   Outline with element, no drag and drop
   Able to open big files (>20MB)  
   Plugin for Clarity

--Eclipse Indigo+WTP
   By default not able to manage big xml files
  Outline view with XML elements, Able to drag and drop elements from one file to other (in different Eclipse windows)

 Eclipse XML Editors and Tools
  org.eclipse.wst.xml_ui.feature
  org.eclipse.wst.xsl.feature

--Notepad++
  it is not an specific editor but it has colour syntax and can be used for:
   -compare two files (plugin compare)
   -see tree view (plugin XML Treeview)
   -pretty XML, check syntax,etc... (plugin XML Tools)
   -find text strings and apply different colors to them (Plugin analyse)

--PSPad
  it is not an specific editor but it has colour syntax and can be used to compare two files(Tools, text Differences)


Web services
Create XSD from web:
http://www.xmlforasp.net/CodeBank/System_Xml_Schema/BuildSchema/BuildXMLSchema.aspx
XSD in Russian Doll Style or Separate Complex Types

!note.  resulting XSD is not proper to map Clarity instances, value is missing.

Flame-Ware Solutions XML-2-XSD v2.0
http://www.flame-ware.com/Products/XML-2-XSD/
!note. resulting XSD has xmlns:msdata, not proper to map Clarity