If you ever want to test your brain's limits on color discrimination, try sorting a few hundred resistors. Was that a blue stripe or a black stripe? Was that a brown stripe or an orange stripe?
While this process was completely maddening at times, it's great to have all my resistors organized. I separated them into these cups, and then put them into tiny baggies, labelled with Sharpies.
Now my components cabinet has two resistor drawers: 1 Ohm through 1k Ohm, and 1.1k Ohm through 1 Mega Ohm.