This is old code, written around 2005 or earlier. This was written in VB5 as I was trying to work out some date-finding code for an Excel timesheet. The project was a success, and to this day I use a variant of this code in an Excel timesheet for work.
This is strictly here for historical purposes. The code here taught me a good bit about bucketchains and I've ported a version to PHP for a calendar app.
This code is free to anyone who wants it.