For those of you interested in all sorts of various Sudoku puzzle variants, the following PDF article might be of interest:
All puzzles in the Dutch 2010 Sudoku championship.
This is an article from a Dutch newspaper containing all the puzzles in the Dutch 2010 Sudoku championship with solutions.
The article is in Dutch, but understanding the text is unimportant.
The winner and reigning Dutch sudoku champion is Bram de Laat, aka Para.
He has also participated in an international Sudoku championship.