Excel Macro for Readability Statistics

I want to create a macro that will determine the "readability" of the text within a given cell.

By "readability" I mean the Readability Statistics that Word returns after a spelling-grammar check: Flesch-Kincaird Grade Level, Flesch Reading Ease and percent of Passive Sentences. I don't care whether Word is used to generate these statistics or an online tool such as http://www.standards-schmandards.com.../rix/index.php.

Separated by pipes the columns of my spreadsheet would look like this: Author | Writing Sample | Flesch-Kincaird Grade Level | Flesch Reading Ease | Passive Sentences

Any advice?