M-Powertools Point 2 Point Spacing Tool
If you always have a heck of time trying to figure out equal spacing for things like coat hooks and shelf locations, check out the Point 2 Point Mk2 layout tool from M-Powertools.
The Mk2 is an accordion-like apparatus with seven adjustable marking points. Just stretch it out so the distance between the marking points (or every two or three marking points) is the proper space you need, tighten the pinch bolts and mark the locations on your project. You can also use it to space fasteners, find center points and figure out how many small boards you can cut out of a larger one.