Don't let bathroom breaks be a bore. Use your time productively by playing sudoku. This Poop Time Puzzles book contains 400 giant size sudoku puzzles. Each puzzle fills an entire letter size page. Give your mind a good work out along with your bowels. If you get stuck you can work it out with a pencil.
One puzzle per 8.5" x 11" page with solutions at the end. Look out for other Poop Time Puzzle Books.