So far I've been using a commercially available pill box, but with some downsides: it's larger than it needs to be, with 4 compartments per day, where I need 3.
I'm also working on a pill-dispensing machine, and I needed a way to make sure the container is in the right place for filling it - which I can use the magnets for.
Update: I've designed a box to store a weeks worth of these containers: https://www.printables.com/model/928468-box-for-magnetic-stackable-pill-containers
The author marked this model as their own original creation.