I didn't find a thread for this. Let's start a list of things crafters will buy for their crafting craftiness:
Anything with gears, lenses, pieces of clocks, leather bits and straps - very steampunk.
Rivets, anything early Industrial Age - dieselpunk.
Scrabble tiles, board game pieces. The game boards themselves. Old dart boards.
Typewriter keys. Keyboard keys.
Windows with wood frames.
Shutters are huge among the craft folk. They make all kinds of stuff from them.
Hinges, cabinet pulls, handles, hooks, doorknobs, cabinet hardware. I just saw some rusty hinges selling for $18 EACH in one vintage shop. Each. Not even for a set of hinges. And in a regular junk shop, hinges were going for at least a dollar each.
Corks. Esp ones made of actual cork, which is getting less common. But they all sell in bulk.
Even beer caps in good shape (unsquished). I found a resale mall where a person had put together little plastic buckets full of interesting bottle caps, $10 for small buckets, $20 for large ones. I don't know what people do with these, but I don't have to.
Household paint cans of all sizes, empty with dried paint in interesting colors, with lids.
Any old farm, garden, or kitchen implements. Old flathead screwdrivers with wood handles.
Buttons and other sewing notions. Thread spools, esp wood. Bobbins.
They also scavenge lace, embroidery patches and other interesting details on otherwise unrecyclable clothing.
Silverplated anything, esp trays and serving pieces.
Old jewelry boxes.
Broken costume jewelry. All the parts get taken apart by these people and put into new items.
Old patches from clothes, esp name tags from gas station type shirts.
Cast iron trivets, cast iron cookware.
Metal 'industrial chic' furniture is big for use in artist studios.
Pine cones, sycamore cones, magnolia 'cones', corkscrew willow branches, burlwood, yucca stalks, driftwood, cactus wood spines, kittenwillow branches, mesquite pods, etc.
Tiles, even broken tiles and broken dishes - they put the broken stuff in tumblers and spin them to make smooth stones for crafts and in gardening beds. Also they use broken stuff in mosaics, like for table tops or wall hangings, serving trays and plaques.
Edited to try to say kittenwillow branches, since it won't let me say *****willows.