Newton message pad? heck even touch styles have been around since the 70's
The base technology is just starting to catch up with the dreamers. Microsoft was promoting tablet edition windows XP in 2002. It took until 2010 until the tech caught up to the promise(and even then it still has a lot of things to improve on.
Quad copters have been built and flown since the 1930's but the tech was always just lacking. it took computers to create fine enough controls to stabilize the flights enough to be practical. In coming Decades we are going to look back at the various flying machines of the 1950's and 1960's and build them with new tech. The base ideas are the same it is the material science, sensor designs, small enough transistors that has drastically improved to make old ideas practical.
Look at the V-22 Osprey. That machine literally couldn't fly in the 1980's they couldn't quite get it to work. It took 15 years of additional refinement to make it practical.
3D printers aren't quite there yet. the material science is still working on it. But it is a good start.