My husband has a room that he uses as an office and a studio. He took out all the old lathe and plaster and partial cellulose insulation. After building out the wall studs to 6 inches, he insulated, vapor-barriered, sheathed in OSB, applied pine paneling, painted and over-stained. The wall now look great and it is the warmest room in the house.
He's also gotten rid of a lot of other stuff. The electronics de-clutter began because he wanted to get rid of a metal secretary cabinet that had sorts of old things in it: a couple of inkjet printers with their dried-out cartridges, cables, dried-out dry-erase markers. I had a bag of obsolete computer stuff upstairs.
Then when we began putting the pile together so I could move it to the car a half dozen more boxes and things came out of the renovated room: an old music keyboard with one irreparable key, a subwoofer, a couple of speakers, a box of auxillary cards, a box of old modems and cables, a small bag of old inkjet cartridges. It filled half the cargo space of our Honda CRV.
At the hazardous waste depot they had a big box for computer electronics, another big box for other electronics, and the inkjet cartridges had to be dropped off at the station that took paints, stains, and household petroleum-derivative products.
The car left pleasantly lighter and we have more space in the house.