Mum loves Sudoku, and I love programming, so to combine the two and make the acquisition of new puzzles cheaper, I created SudokuMaker.
This simple Python script uses the reportlab module to generate pdf pages that have three Sudoku puzzles on the left, and their solutions on the right. By folding the paper lengthwise, you can first work on solving the puzzles, and then unfold the page to check the answers.
When started the program asks how many squares to leave empty per puzzle, and how many sheets to print. It then generates that number of pages, and prints them on the default printer. After that it pauses, to allow you to flip the pages over and print a second newly generated set on the back side of the pages.