I was building a battle box out of War of the Spark, one of my favorite sets. Other than the box itself, I wanted each deck sleeved in some cheap sleeves, and burger token deck boxes are perfect for holding them. The 60S boxes have room for 60 single-sleeved cards plus a reference card and a few tokens, and I was able to easily add a custom label to the side of the transparent box to know which deck is which with minimal hassle.
I actually use burger token boxes for storing burger tokens as well! As I head home for the holidays, I can easily fit a couple of decks in a few boxes and then use another box for storing tokens / dice in the same form factor, making it really easy to build flexible custom travel cases.