Get (free) XSLT intellisense in VS.NET
Note: this entry has moved.
This is not really a new trick, I must say up-front. In order to have intellisense on XSLT documents you must copy this XSLT schema file into the folder C:\Program Files\Microsoft Visual Studio .NET 2003\Common7\Packages\schemas\xml.
Restart the IDE and you're done. Enjoy!
Credits:
FeserSoft, who developed the schema.