To echo others - go vertical. The first step is a riser on a cart, that allows you to put the small delicate items above the fray, and to work on the main level, while increasing the cubic storage without increasing the footprint.
I stumbled onto these Basnik carts at auction and liked them so much I bought more new ones. I have all manner of carts built and bought used, these are the only ones I've liked enough to buy new. In effect these can become 'Where things get put away" and a workspace cart at the same time. This one is mostly workspace.
Note the fast food trays on the bottom shelf, they are great for gathering up a bunch of clutter and moving it, then rapidly bringing it back when the space crisis is over. Also keeps ballscrew balls from rolling away, etc.
This one is mostly storage. Full of chick vise stuff, it stays in one spot but can be easily moved to where needed, or just to access the machine behind it.
This one is both storage and workspace, the middle shelf is clear to receive WIP and raw material/bar stock and it is easily moved when needed to access the machine behind it for attention (cleaning or service).The rest of the stuff there is waiting for permanent space to be made somewhere, in the meantime it's not in the way and can easily be moved en masse when needed
These carts are terrific for a place to put "in process" tools for temp storage, they combine the storage space of shelves and the utility of rolling carts. There's no wall space left here for shelves, this allows the 'shelves' to be placed where you couldn't put permanent shelves, allows you to bring the shelves to the work, and lets the rolling cart BE the 'place to put things away'.
I've also seen custom racks built for them to hold long items vertical, hooks for hose belts and cables, tubs for liquids, etc.