I bet no one remembers the ramp walkers! Back in the 1960’s when battery operated toys were normally an expensive dream the ramp walkers took full advantage of clean free gravity.Made by Marx Toys mine was a Yogi Bear & Huckleberry Hound Ramp Walker.
They were easy enough to use, stick them at the top of a small ramp and let them go, they would toddle along down the ramp like a grandmother on a zimmerframe. The ramp walkers were normally made of plastic and around 8cm tall. There were several other Hanna Barbera characters used but this one was my favourite ramp walker.