Book excerpt: What better way to boost your mental fitness than with sudoku? Sudoku has taken America by storm! Try one or two of these sudoku and you'll discover what millions of fans already know: There's nothing as fun as sudoku! Features: · 100 easy to hard sudoku puzzles · Edited by legendary New York Times crossword editor and "America's puzzlemaster" Will Shortz · Big grids with lots of space for easy solving