I like the Super Satchels boxes by Art Bin. They stack well and are sturdy. They have handles and secure latches and can easily be picked up and moved. I use both the smaller and bigger ones. I can use the smaller ones for regular size threads and the big ones for cones, and I can also use the big ones for a collection of threads of one type, etc. I have thread separated by types first: cotton, polyester, rayon, specialty threads. Then by either warm or cool. This works well to keep out dirt and dust and it's fast and easy to find the color I need. I am slowly replacing my snapware containers, which are a great size but way too flimsy. I keep the thread boxes on wire shelves in my sewing room.