This post is awakens a wonderful opportunity to learn what folks are re-purposing for parts storage.
First and foremost, I buy 99-cent 6-quart plastic shoe containers at Walmart. I label them with masking tape and use them to store track items (10" Real Trax straights & o42 switches will fit), electronics, scenery materials, rolling stock projects, etc. These containers stack nicely and look good on the inexpensive plastic shelves you can buy from Home Depot, etc.
I reuse the white plastic containers with clear lids that Chinese food comes in. I find these ideal for storing project parts that are too small for the shoe containers.
Third are the small (1/2-ounce) plastic measuring cups that come with some medicines (cough medicine). These are ideal for mixing small amounts of latex paint, and for cleaning tiny parts with rubbing alcohol.