Sometime ago I picked up 4 square 5 gallon cans at an auction (old oil cans). After moving them around for a year or two I decided to put them to use. I cut about 2/3 of the top out and stacked them on a shelf (like bolt bins). One holds pipe, one holds square, one for angle and one for rods.
Anything under 12" goes in a bin, Anything longer than a foot goes on a shelf simular to your picture, Longer than 3' goes in a barrel. 6' on the rack.
I suspect one could use buckets too.
Bigger question is when to stop keeping it. Bout every other project that has me digging through the bins, I sort out the smallest duplicate pieces and throw them in the scrap pile.