I don't know about top three but in the medical field I would have to say the artificial kidney would have to be up there. For people who cannot find a donor match, it buys tremendous time to find a living donor. Don't believe the intent is to utilize an artificial kidney permanently but can be used for a lengthy period of time reducing dependence on dialysis, etc.

The other in the medical field would have to be the laser scalpels that can do precision deep brain surgery. They have revolutionized brain surgery and allowed removal of tumors previously inaccessible to surgeons.

Can't think of anything more valuable than inventions that preserve life.

1870 through 1970 saw some amazing stuff invented. Take the transistor, for instance (invented, IIRC, in 1948). From that, we get these amazing chips with 4 GHz clock speeds, plus parallelism. It's all transistors...

... except that we didn't have such chips in 1970. We had, what, the Intel 4004?

That is, for things invented from 1870 to 1970, we have had at least 45 years of development after invention, and perhaps as much as 145 years of development, for those inventions to reach their full potential. Things invented in the last 20 years? Well, by definition, we haven't had more than 20 years of development after the invention. We're still where transistors were in 1968. At that time they were beginning to appear in radios, and had some use in mainframes, but there was no sign yet that they were going to completely dominate the world.

What could the current stuff be? Some AI techniques invented in the last 20 years could become huge. CRISPR might.

By the way, it's also kind of unfair to compare the amount of invention that occurred in 100 years to the amount in 20.

I think the CRISPR technology is going to play a huge role in the next 30 years.

1. Smartphones 2. their apps 3. their business models

Although the biggest success are also harmful to society (Facebook, Google, Uber, Airbnb, etc), they are changing the way we live radically and fast.

Is AirBnB harmful for the society because it decreases the demand for hotels, or what is the thought process here?

It's harmful to hotels, but the argument is that the AirBnB sellers and consumers get more benefit than hotels lose. Increases in efficiency should result in a net benefit to society. Assuming perfect information, free-markets, yadda yadda.

This isn't correct. The major problem with Airbnb isn't that it competes with hotels, it's that full-time residents have to compete with Airbnb for housing.

Airbnb owners typically violate local laws preventing short-term rentals in residential properties. Short-term renters have a higher willingness-to-pay than long-term renters, and it currently makes more financial sense for me to rent a 2-br and Airbnb one room than to have a room mate or get a 1-br. There is now one less room in the housing stock of my city for long-term renters, thus driving up the cost of living for people who live in the city full-time.

This is more like the harm to society I was talking about, but there is more. Small hotels and b&b are an important part of touristic cities' economy, when airbnb get to drain most of the $ coming from tourists you'll scramble local economy. Booking have the opposite effect imo (it is like uber x taxi apps).

Absolutely, but a city needs a stable rental market that isn't subject to the vicissitudes of tourism/travel demand.

The modern electric car (I say modern because the first electric car was supposedly built in 1880). No doubt the end of the combustion engine and the end of reliance on fossil fuels will change literally everyone's lives to some extent.

In my field of work, Linux, GitHub, and the appearance of modern programming languages like Java, Go, hard to pick a single language but they are all changing the industry in their own way, hopefully for the better.

In terms of Gordon's "Is U.S. Economic Growth Over? Faltering Innovation ..."

The big change that's in progress of being developed is AI. Instead of taking x man hours to make a car it'll take something like zero because the AI robots will do it. Not quite there yet.

Bitcoin

Bitcoin is cool, but I think people are over playing how revolutionary it is/will be.

If there is one currency for the entire globe, it is revolutionary.

Or a money burning machine if the algorithm sucks. :)

You have to back test before punting a single penny in the stock market... for me the idea to invest or trade anything without back testing the strategy with 20 years of data is pure gambling...

Slice bread?