Attached is a sudoku solver in the form of an excel spreadsheet with macros (ignore the warning and enable the macros). I wrote it to prove that sudoku is merely a task of repeating simple tests over and over again, and never requires complex logic. Plus it helped end my addiction to sudoku. It will solve sudoku step by step for you and allow you to choose which tests to use to solve it. It also highlights how each square was solved and gives insight into how it is working.

Please give people a link to here so they can download the latest version rather than emailing it on.