Hard not to get into full shilling mode here. Been part of the community since 2014. I've very excited that this project is stepping out of the shadows after many years of tech development.
It has been frustrating at times seeing a small team and small community working on something that is so ambitious and get so little acknowledgement of the efforts. Mind you the interoperability vision was there in 2014!
This project is all about true decentralization and about overcoming the tribal attitude we've been seeing in the crypto sphere. It's run by community members, some of who have paid functions like the devs.
It's about connecting the the communities of each project and allowing the great tech of each project to be shared with a much greater ecosystem.
Blocknet is a protocol first, a critical part of inter-blockchain infrastructure as you will. They allow data to be exchanged between blockchains.
The first Dapp is their own decentralized exchange, BlockDX. This uses the protocol to check if traders actually have the funds available to trade with each other and it allows for value to be interchanged between chains too.
The trades are done thru cross chain atomic swaps. It is true wallet-to-wallet trading. Current state is a Beta. But get this: Trading fees/ protocol fees are distributed to BLOCK holders.
There is not company! BLOCK is needed as a trading fee and will be market-bought on the dex. This is the reason why you want to own some. It creates buy-pressure automatically with adoption.
Mind you the current state is a beta. Currently you'll need to download full chains for coins you want to trade. But that's also why the blocknet community is hyped about the release of Xrouter.
That will serve as the backend for any SPV (lite) client or ultimately a multiwallet that doesn't need to download the full chain.
To get back to the protocol, imagine being able to build dApps with features from multiple chains. Being able to charge and pay microfees in any cryptocurrency for the services you offer.
If you are a dev, or have a sweet dApp idea, just start cherry picking the features you want from any chain and offer it to your target audience.
Also, with release in July ERC20 will be supported (using 0X)
To sum it up:
https://youtu.be/9QnH0dGNBvIAtomic swap demo between Zoin and Block
https://youtu.be/DGJRxyWGvo0Xrouter demo:
https://youtu.be/2WOpBEkTHgkROI musings from another community member
https://steemit.com/blocknet/@theblocknet/from-one-investor-to-another 
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