According to the internet, this is the original slinky commercial. My favorite thing to do with my precompressed helical spring toy as a kid was to make it "walk" down the stairs, by bending it over the top step and then watching it work its way down to the bottom, as shown in the commercial. Slinky users: what was your favorite thing to do with a Slinky?
Slinky was also the inspiration for Log, a fake commercial on the Ren & Stimpy show: