Edit NAnt build file in Visual Studio 2005 with intellisense

install lastest nant from http://nant.sourceforge.net/. Install help: http://nant.sourceforge.net/release/latest/help/introduction/installation.html or search nant.bat.
Copy schema file from nant/schema/nant.xsd to C:\Program Files\Microsoft Visual Studio 8\Common7\Packages\schemas\xml\nant.xsd
Navigate to  HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\VisualStudio\8.0\Editors\{412B8852-4F21-413B-9B47-0C9751D3EBFB}\Extensions
Add a DWORD name of build and value of 29 hex.
Create the build file by convention it’s named as project_name.build.
Use Visual Studio to open the file and add the following:
<?xml version=”1.0″?>
<project name=”your_project_name” default=”build” basedir=”.” [...]

Visual Studio Productivity Tools

Power Toys for Visual Studio http://msdn2.microsoft.com/en-us/vstudio/aa718340.aspx.