This 1965 NatGeo ad for GM's "Tomorrow-Land" exhibit at the 1964 World's Fair makes me go all dribbly for a time-machine: "You can look over GM's exciting 'idea' cars -- Firebird IV with television, stereo, game table, refrigerator; GM-X with jet aircraft cockpit and controls--fascinating design and engineering innovations right out of tomorrow. You'll take a ride that is wrapped in wonders . . . through the metropolis of the future, over Antarctic wastes, into tropical jungles, along the ocean floor."