Unless you've got a hydraulic lift, a mechanic's creeper is an indispensable tool for getting underneath a vehicle. But you've got to be on a smooth surface to use one, and ensure there aren't any air lines, extension cords or tools in your path. Plus there's a height issue with low-slung vehicles. And creepers can be awkward to store.
Well, here's the Magic Creeper, which serves as a great example of how understanding a material's properties can be used to re-think an object entirely, and solve a host of problems:
The following videos have been included partly for SEO reasons but mostly because at least one of my bosses is on vacation and not checking the blog.
Also, some of my favorite covers: