I love the idea of having book shelves built into small hall spaces like this arch in the hallway
Dorm // Shelves & filing systems for small spaces
Concealed Desk Cupboard Workspace With Shelves - Small Spaces Ideas (houseandgarden.co.uk)
Shelves For Pantry Door ~ Spice Rack Built Into Pantry Door
mud room built into a pretty small area. Shelves, hooks, drawers, seat, basket/shoe area, plus add'l storage above shelf unit.
Home Sweet Home
Apartment Therapy's Big Book of Small, Cool Spaces