If you like to cook you will likely have an unruly spice cabinet. By using scrap wood and very little effort you can tame your spice supply.
Step 1: What to Do
Take your scrap wood--it could be as light as 3/8" plywood--and mark the size of your old shelf on it. Make the shelf into a blocky U shape. I made my shelves 2.5" wide. Cut it out with a hand saw, jig saw, or whatever you have handy.
Step 2: Smooth
Smooth out the edges with a sander. No need to scrape your hands accidentally when reaching for spices. Splinters from cooking related injuries will raise eyebrows.
Step 3: Before and After
Bam! Look at that! Easy to see what you've got and easy to get in and out. A big benefit is that you'll not be buying spices that you already have . . . but don't know that you have because they're hidden by the spices you use most often.