There's no simple answer to the question of which .NET components can be used from scripts. MSDN does have some documentation about how to write .NET components that can be used by COM applications—but "Exposing .NET Framework Components to COM" (http://msdn2.microsoft.com/en-us/library/zsfww439.aspx) is more useful to programmers than to administrators. Fortunately, there are some simple ways to try particular .NET classes and some rules of thumb to determine if they're usable from scripts.
If you're not familiar with .NET classes at all, you can begin by browsing through ".NET Framework Class Library" (http://msdn2.microsoft.com/en-us/library/ms229335.aspx). That page provides links to .NET namespaces, each of which contains one or more classes. If the class documentation's definition includes a ComVisibleAttribute that's set to True, you can try creating it within a script by using CreateObject. Use the fully qualified .NET class name as the programmatic identifier with CreateObject. . . .