I have a slotted oval board that holds my most used rulers on the desk that my sewing machine is on. I have taped a seam ripper to the right side of my sewing machine with the cap upside down so that it is always there. I also keep a small scissors on the right side of my machine next to the pincushion/string catcher.
I have a clear plastic cart under the desk...top drawer hold rotory cutters and blades, measuring tapes, bobbins, small scissors...Middle drawer hold tools ie..screw drivers, pliers, brushes and my big scissors.. bottom two drawer hold my cone threads.
I have a double sided tool case for my regular sized threads..holds 48 threads.