Futurology: Past Technologies

Note: This article argues that technologies may be hard to predict ahead of time and that few technologies have failed. If you wish, please challenge the assertion made here at the discussion page.
==Technologies for Each Letter in the Alphabet==
Have there been any significant failures in past attempts to solve a problem using technological means (i.e. achieve a difficult new technology)? There are extremely few examples (such as ornithopters), but even in those cases the goal (flying) was simply achieved by different methods.
But what about goals of technology that were once thought by most people to be impossible or forever impractical, but that in fact were achieved? --or that were previously not even IMAGINED, and yet were achieved? They are many and notorious, including:
===A to D===
Abrasives. Air conditioning and two-way heat pump. Air to air missiles. Algebras. Alloys. Alphabet. Anaesthesia. Analgesics. Analog computers. Anatomies. Antibiotics. Antidepressants. Armies. Artificial insemination. Asepsis in surgery. Assembly line. Auger. Automated factories. Automatic gene sequencing. Automobiles. Adze. Axe.
Babies from frozen embryos. Baking soda, baking powder. Ball bearings. Banking. Bellows. Blacksmithing. Blood and urine analysis. Books. Bow and arrow. Brazing. Bricks. Bridles & saddles. Bubble level. Butter. Buttons.
Calendar. Camera. Canals. Catalysts. Cathode ray tube. Central heating. Centrifuge. Chain. Cheeses. Chess program that can defeat a chess champion. Chunnel. Cities. Cloning. Clothing. Coders and decoders. Codes of law. Cogwheels. Comb. Compass for drawing. Condoms. Contact lenses. Coolidge tube. Corporations. Cosmetics. Cotton gin. Counting. Cryogenics. Cryopreservation of blood and other tissue. Cryosurgery. CT and NMR scanners.
Dental amalgams. Dental floss. Dentist's drill. Deodorants. Depilatories. Desalinization plants. Dietetics. Digital computers. Digital disk recorder. Directories. Dirigibles. Distillation.Drawing. Drugs. Dynamite.
===E to H===
Earth satellites. Electric generator. Electric lights. Electric motor. Electric shaver. Electrophoresis. Elevators. Endoscopy. Epoxy. Eyeglasses.
Facial tissues. Fake fat. Fake sugar. False teeth. Farming. Fax. Fertilizers. Fiberoptics. File (paper). File (tool). Fingerprints. Fire making. Fishhook. Fletching. Flint chipping. Flying machine. Flypaper. Forceps. Fork lift. Bulldozer. Forks. Freeze drying. Furnace.
Genetic engineering. Genome mapping. Geometries. Glues & adhesives. Goldsmithing. Growth factors. Gyroscopes.
Hair care. Hammer. Horse shoes. Host mothers. Hotels.
===I to L===
Insecticides. Insulin. Intercontinental missiles. Interferons. Internal combustion engine. Internet databases. In-vitro fertilization.
Jet propulsion.
Kevlar. Knife. Knitting. Knots.
Laminates. Language. Laparoscopy. Lathe. Lawnmowers. Laxatives. Logics. Lubricants. Lying.
===M to P===
Mace. Magnetic tape recorder. Magnets. Manuals of operation. Maps. Masers & lasers & holograms. Metallurgy Microscope. Microtome. Mining. Mirror. Money. Monoclonal antibodies. Moon rocket. Movies, including animation, special effects, and 3-D. Musical instruments.
Nails. Nanotechnology, just beginning. Nations. Navigation and location by satellite.Navigation systems. Needle & thread. Newspapers. Nuclear energy. Nuclear fusion, still in the works.
Oars & paddles. OCR. Offshore drilling rigs. Organ transplants. Oscilloscope.
Paint. Painting. Paper. Paving machines. Paving. Pendulum. Phonograph. Piping & tubing. Planing tool. Planting machines. Plastics. Pliers. Pneumatics. Pockets. Poetry. Polygraph. Potter's wheel. Pressure pump. Prostheses for limbs. Protein sequencing. Pulley.
===Q to T===
Quantum computers, just beginning. Quantum chemistry. Quantum mechanics. Quantum physics.
Radar. Radiation therapy and chemotherapy. Radio telescopes. Radio. Railroads. Refractories. Rivets. Roads. Roller bearings. Rope. Ruler.
Safety razor. Sails. Sandpaper. Saw. Scanning tunneling microscope, atomic force microscope, etc. Schools. Scintillation counters. Scissors. Screw machine. Screws. Sculpture. Scythe. Seismic prospecting. Semaphore. Sewers. Sextant. Shoes. Sickle. Skin grafts. Skyscrapers. Sledges. Smart bombs. Smelting. Soap. Soldering. Solvents. Sonar. Sonograms. Soup. Spectroscope. Spinning and weaving machines. Spoons. Stapling machines. Steam power. Stove. Stylus. Submarines. Surveying. Sutures. Sword. Synthetic hormones. Syringe.
Tables of organization. Tattoos. Telegraph. Telephone. Telescope. Television. Tempering steel. Thermometer. Tilling machines. Tissue typing. Toilet. Toilet paper. Tongs. Tooth brush. Tooth paste. Transatlantic cable. Transgenesis. Transistors. Transit. Traps & snares. Travois. Triodes. Turbines. Typewriters.
===U to X===
Use of radioisotopes.
Vaccines. Vacuum pump. Virtual reality. Vise. Vitamins.
Wallpaper. Watches and clocks. Water pump. Welding. Well-digging. Wheel. Wrenches. Writing.
X-ray diffraction techniques. X-rays. Xerography.
===Y and Z===
Yurt making. Yo-Yo.
Ziploc. Zipper. Zeppelin.
===In Conclusion===
Sure, some of the above are arguably minor or redundant. Still, I think they were all reasonably important in their time, and not obvious or easy ahead of time. But a great many have doubtless been omitted. The important thing is that there have been very many successful projects of technology, and very few or none that have failed.
Based on a list from Cryonics Institute about the probability of cryonics' success.
These days, it is downright difficult to dream up a prediction too outlandish to have some basis in scientific research. Even the wildest leaps of scientific fantasy don’t seem all that implausible anymore. 
Creating whole organisms from the building blocks of a few cells? Been there, done that. Computers smarter than humans? Big deal, done it. A telescope so powerful it can discern almost the entire history of the universe? Yawn. What else you got?
== Links ==
Source: What we know for sure: nothing 
* FlyingCar at Futures wiki
Category:Concepts
Category:Technology