I found the first one under a table at an estate sale, a squat brass thing with a yellowed shade that looked like it had lived through two divorces. Cost almost nothing. Put it on the side table in the living room next to the sofa, turned it on instead of the overhead light, and the whole room went from waiting room to somewhere you'd actually want to sit down. That was the moment. Not dramatic, just a lamp doing what a lamp should do, which apparently nothing in my house had been doing before.
Once you've got one, you start seeing where the rest belong. A ceramic one with some age to the glaze looks right next to a stack of paperbacks and a worn armchair. A glass or crystal base catches the light nicely on a console table with nothing else fussy around it. They sit well against plain painted walls, next to plants that need a bit of trimming, on a bookshelf that already has too many things on it. I've got one on a nightstand that's just a cheap frame from a big box store, and the lamp makes the whole corner look like it was planned instead of assembled over four years.
These suit the rooms people actually use at the end of the day, living rooms, bedrooms, a reading corner nobody photographs. They work best in homes that have some age or at least some clutter to them already, a rented apartment with a lease that won't let you paint, an older house with uneven floors, anywhere that a brand new sharp edged lamp would look a little out of place. They're good company for winter evenings when you want a warm pool of light instead of the big ceiling light, and they hold their own in summer too, something about old brass and a linen shade that doesn't mind the season.
They age well, which is sort of the whole point of buying one used instead of new. The brass gets a little duller, the ceramic picks up tiny marks you stop noticing, the shade yellows further if it hasn't already, and none of it looks wrong. Wipe the base with a damp cloth now and then, keep the shade out of direct sun if you want it to hold its color a bit longer, and check the wiring once if you're not sure how old it really is. Worth the five minutes.
This is for a home that already has some history in it, or wants to look like it does.