Reader Marty Zager writes in: There have been so many times that I'm scrambling around to find a ruler to measure something in my office or apartment, and I'm completely sans ruler.

You can measure most things in the physical world with centimeters ... standard ruler handles both---but it ignores digital environments, which render in pixels, and typefaces, which print in ...

Just choose the shape (dots, lines, squares, or even hexagons), move the slider to adjust the spacing, and print away. The ruler at the top (which I believe is in centimeters) helps with the sizing.