I have A LOT of small cutting/grinding/shaping burrs for my Dremel/Foredom tools, as the photograph will prove. In fact, I have so many that I can't remember them all. Storing them together so I can visually scan them to find the one I need has its own set of problems. Over the years, I've made many wooden blocks in an OCD attempt to get them all sorted in one place. The bit shanks come in two sizes, 3 and 4 thirty-seconds, so two sizes of holes are required. Inevitably, as soon as a block is drilled with the requisite number of each size, I'll acquire more bits and be back at the start.
I finally had enough, overpowered my OCD compulsion, and came up with a quick and dirty fix. Six 3 x 1" pieces of corrugated cardboard were cut. Five were glued face-to-face and the sixth was glued on the bottom to close off the corrugations of the other five. As can be seen from the photo, this allows very high packing density; I didn't have the patience to count but there's got to be 60+ bits in roughly six cubic inches of space.
Quick to make
No hole layout or drilling required
Accepts both shank sizes
Less rugged than wood
May require the use of tweezers to extract some burrs
I'm pleased with the practicality of the solution but my sense of tool artistry is still annoyed.