Today’s partfinder isn’t an electrical part, or even a storage solution, it’s a notebook. National Brand #43648 Computation Notebook, to be precise. The greatest engineering notebook of all time. I have several dozen of these — one for each (non-humanities) course I took in college, plus many more filled with different project notes. I love these books because they’re well made and durable, and the pages are 9.25 x 11.75, so you can easily paste or tape A4 sheets inside. Excellent for engineering or math class notes, or project sketches, measurements, etc.
There are several different kinds of computation books available: spiral bound, three-hole, etc. I like this square-bound type the best because you can ‘crack’ the binding and make it lay flat — very helpful if you’re left-handed.
These are available sometimes from larger office supply stores, but you can always find them on Amazon — check ‘em out in the partfinder!