Old microphones
Some of us sang into hairbrushes while others used a real microphone. If you have a vintage microphone laying around, you could find a musician or music producer who would be willing to spend for it. Rare finds like the Neumann U-47 from the 1940s are worth tens of thousands of dollars online, Orkin says. But the vintage microphones most people are likely to find stashed away in a box is from a maker called Shure, which could probably fetch around $50, Orkin says.