If you use a dashcam or screen mounted GPS in your car, keeping the cables controlled can be a real pain. Here's a simple fix.
A little while back, I had a whole bunch of dashcams to test for a review, each with their own cable to connect to a car's cigarette lighter for power.
They worked, but because my preference for anything on my windscreen is to have it to my right, this meant that the cables trailed across the dash and frequently slipped down when the car was in motion. Not the worst problem in the world, but annoying and sometimes a little distracting, which isn't a good thing when concentrating on the road.
My solution? Those adhesive-backed hooks that you can buy in multi-packs for hanging pictures or similar on walls, affixed to the dash at a decent point for tensioning the cable and keeping it in place. They're inexpensive, unobtrusive and because the adhesive is usually non-permanent, if you find you aren't using the dashcam or GPS extensively, they're easy to remove as well.