I have a couple of short ethernet cables and an HDMI/HDMI that's also maybe 8' long stashed in the garage, so they're probably headed to donation. There's a 25-foot ethernet cable that I used to connect one of my Bride's systems before I went full-bore WiFi; I just noticed that I've still got that cable running around the perimeter of the room, but I'll probably save that just in case.
What I was looking for while rooting through the junk was a 15' HDMI/HDMI that I could ideally fish through the drywall to connect the Chromebook to a large screen for occasional streaming. I don't have one that long that's rated for in-wall, but I will in two days. $10 is what it would run, but I got it for 53 cents due to credit-card points I'd forgot I have. Sweet.