I use the largest size leftovers containers (gladware or similar) and sort the spools by color family. I keep special threads (metallics, invisibles, etc) in their own contaners as well. They stack beautifully on a small shelf next to my sewing machine and tags make it easy to find what I need. I also keep notions in the same kind of container (one for needles, one for fabric chalk and markers, etc. etc.) Inexpensive, looks halfway decent, and it keeps my stuff from getting dusty!
Love reading al these great solutions!!
Laura