this is a list of technologies that were known and understood in the 1990s but not acted on, for Mysterious Reasons.
in many cases these opportunities are still languishing in obscurity.

- self landing rocket booster stages
- dental caries vaccine
- evacuated tube transport (hyperloop)
- local robotic automated restaurant food prep
- fully automated bulk food dispensing warehouses
- self contained methanotrophic food production ecosystems
- algae omega-3 ice cream
- actually funding a rapidly reusable space plane
- suborbital intercontinental transport (mockingbird)
- straight to your basement delivery pod tunnels
- reconfigurable FPGA computing
- holographic data storage
- ketogenic diets
- powered exoskeletons
- stamped stainless single piece dymaxion bathroom
- packaging toilet
- prefab housing
- hexayurt style disaster relief housing
- mold-free construction materials
- personal submarines
- personal VTOL aircraft
- geothermal heat pumps
- a moon base
- conditional pledge escrow (kickstarter)
- functional programming
- magnesium supplementation (finland nusalt)
- ocean thermal energy conversion
- ship kites
- ruminant herding
- breeding mice for cryonics survivability
- helium conservation
- actually funding anti-aging research
- actually funding molecular nanotechnology research
- low earth orbit internet satellites (teledesic)
- human growth hormone supplementation
- banning tylenol
- stainless steel automobiles
- unschooling
- hybrid fusion-fission nuclear power
- accelerator-driven subcritical reactors (nuclear energy amplifier)
- cold fusion research
- actually thinking about global warming
- seabed mining (manganese nodules)
- marijuana decriminalization
- proof of work spam prevention (hashcash, penny post)
- active suspensions for automobiles
- radar for automobiles
- cross polarized windshields and headlights
- hindered amine light stabilizer UV inhibitors
- pillow dome greenhouses
- banning shark finning
- banning old growth logging
- partial gravity health effects research
- full mammalian life cycle in zero-g
- basalt fiber composites
- cheap low-grade titanium smelting (CSIRO process)
- breeding chocobos
- public skate parks
- letting gas turbine racecars compete
- rocket turbine engines (turbonique)
- rotating momentum exchange tethers
- flatbed scanner large format digital cameras
- flat panel CRT displays
- grating light valve displays
- multitouch light pen human computer interaction
- stewart platform haptic feedback
- holographic optics
- human cloning