When I saw a Serial-to-USB cable at a thrift shop 10 years ago, I wasn't sure if I'd ever have a need for it, but it was new and only $4 so I bought it. It recently came in handy as one of the pieces needed to run a Windows 3 program that came with a deluxe Radio Shack multimeter from the 1990s. About a year ago, I bought the multimeter which featured an RS232 connection, and a floppy with a Windows 3 "ScopeView" program that would let a PC record and visualize its output. At the time I didn't have a Windows machine. A few months ago I bought a 2006 MacBook Pro, and put a 1TB mechanical drive with a Vista partition in it. I recently had time to put it all together. The last piece was getting the cable driver from the manufacturer. It felt good when everything was working. One small problem was that the driver makes the USB ports unique. After setting it up to work with one USB port, it won't work when plugged into a different port.