Interesting bit of silly philosophy today...what IS the best practice in .NET when you are given things like useful financial functions (Rate(),  Pmt(), etc...) that have been pulled forward from VB6 and given the same function signatures in VB.NET?  Basically the whole Financial library of intrinsics from VB5 and VB6 is available in Microsoft.VisualBasic.Financial (class, not a namespace).  From a design standpoint, is it cool to just have a C# assembly reference over to Microsoft.VisualBasic.dll?  Is it overkill to provide a little "insurance" by first encapsulating the Financial Functions in a VB.NET Class Library, then referencing or inherititing from THAT in C#?  Can we count on Microsoft.VisualBasic.dll and Microsoft.VisualBasic.Compatibility, etc to be around a while? Hm...