Check out the IIS 6 Resource Kit; it's got some cool tools for administering your new IIS 6 (Windows 2003) server. You can get it from Microsoft here.
I discovered this kit in the process of debugging a Response Buffer problem on the applications we migrated from IIS5 to IIS6, Dave Burke has blogged the same sort of experience (and the solution I arrived at, too) here, so I don't need to get into the MetaBase explorer.
The Resource Kit has some cool tools for testing and analyzing a web server!
Happy .Netting!