This one is a bit pricey, but it's just perfect for micros. I only use these
for my best specimens.

There is a seemingly unlimited number of different and reasonably priced
bead storage cases. Any of the craft stores carry these.

These come in different sizes and shapes at a low cost. Clear containers
make it easier to see the contents. I like the shorter ones as they'll fit
easily under a microscope.

These are one of my favorites. A little pricey but are real nice for
use with a microscope. This is a 15 card holder, one of many available
sizes.

Magnifying  Plastic Boxes

These sound great but the magnification is useless, just an expensive
plastic box as far as I'm concerned

Coin holders and small plastic bags help keep everything
organized.

I recently started using quarter coin holders that are self
adhesive and I like them better. No more staples, downside
is cost and reusability.