The rise of new economies
The Parc de la Villette is where the Paris slaughterhouses used to be. It is now the third largest park in the whole city.
Transformed unrecognisably, it has become the home of a huge science museum and many cultural activities.
It is one of the mighty "grand projets", the huge public works schemes inspired by the late President, Francois Mitterrand. Very French.
For some weeks this autumn, the Parc was also the temporary home of a provocative exhibition called Wave: How Collective Innovation is Changing the World.
It was a collection of photographs and demos of start-ups and projects from many places around the world.
It has now closed in Paris, but look out for it popping up in other cities in the coming months.
Wave is backed by the French bank BNP Paribas.
It is a celebration of many ideas made possible by the new connectivity of the internet. That's why it's provocative.
Nobody can yet say what will result from the great internet disruption, which is still in its birth stages. It's a good idea to look at some of the outliers; they may be pointers to our disrupted future.
Among the different ways of doing things on show in the flashy Wave tent were emergent things such as the "sharing economy", where people share their scarce resources (homes, cars, time) with others for financial benefit.
Great big new companies such as Airbnb and summon-a-driver services Uber and Lyft are making a controversial name for themselves in many countries in this sharing economy sphere.
In France (and other parts of Europe, including the UK) there is BlaBlaCar.
Started by Frederic Mazella 10 years ago (after he was too late to get a train ticket home for Christmas), it's an online service putting people who want to go somewhere in touch with drivers going their way - so that they can share costs but not make a business out of it.
The "bla bla" bit of the name is supposed to reflect the interesting chat driver and passengers can share on the way. On the website you can choose how much of that you want.
After 10 years of development, BlaBlaCar is past the start-up stage. It recently raised $100m (£64m) in a funding round to enable it to boost international growth before copycat rivals get in on the act.
Inclusive and informal
Another new economy phenomenon is the "maker movement", where many people with access to creative tools are discovering the joy of making things they might previously have bought.
If they come up with a really ingenious idea, there are a lot of new ways of getting money to create inventive products and services, utilising the internet power of crowdfunding and crowdsourcing to make one individual's efforts go further, faster.
In theory, thanks to these new business creation tools, who needs capital to start a business?
Then there is what is called the "inclusive economy", addressing what the late business professor CK Prahalad called the billions of people at the bottom of the pyramid.
For a long time they were underestimated by most observers as merely part of what used to be called the "informal economy".
They may not pay taxes, which is what "informal" seems primarily to mean. But in many developing countries the liveliness of the informal economy in vast slums and shanty towns puts the recognised formal economy to shame.
There is also the "circular economy", where used stuff is recycled not dumped.
This is a potentially fundamental challenge to the 20th Century production line mentality that ends in bulging landfill when consumer goods run out of useful (or fashionable) life.
All these collaborative ideas have at least some potential to reshape our familiar, conventional world, mobilising the extraordinary cheap connectivity of the internet. A wave of new activities that gives this show its umbrella title.
Wave was designed to provoke visitors into thinking more about the wave of change that's disrupting many established business practices. BNP Paribas is backing it because it thinks this new economy is something it has to understand and participate in as a bank.
Wave is curated by the Indian-born innovation consultant Navi Radjou. He now lives in Silicon Valley, California but teaches at the Judge Management School at Cambridge University.
He's an enthusiast for Jugaad innovation: Jugaad is the Hindu word for "frugal". It reflects the way innovation is often done in India: bottom up, inventive, and much cheaper than the way a big company traditionally throws resources at things it wants to change.
Mr Radjou says: "The post war industrial models - big research and development budgets, corporate hierarchies, etc, are not appropriate for the complex world in which we live today.
"Let's use our human ingenuity to build an innovative and sustainable society."
That is what has been on show at Wave.
Mr Radjou defines this as "engineering with common sense". Our profligate 21st Century needs a lot more of it.