Luca Bolognese recently posted a new library that makes Excel’s financial functions available through .NET managed code without going through Excel! This is excellent news for anyone working on a financial or LOB app. Luca created the library to mimic the Excel functions, including errors or bugs, in F#. The release comes in two versions: a smaller .dll that will run on an installed F# installation and a larger, stand alone .dll for those who do not wish to deploy F#.
Check it out at the MSDN Code Gallery.