I’ve been trying to find one and can’t, but it hasn’t stopped major corporations like IBM, who I would expect to jump on the hype train, but even AWS is embracing it to a degree with their latest announcements.
Blockchain-the-trustless-consensus-protocol has a fundamental challenge that makes it completely and utterly pointless for most applications — the oracle problem. You build up a whole system around a secure trustless chain-of-custody, but then require trust in some sort of outside entity for adding resources into the system. If you're willing to trust that entity, there's many simpler ways to sort out your chain-of-custody problems.
Cryptocurrencies "work" precisely because they don't need an oracle. They don't track anything that exists outside the chain.
Trustlessness is a property of Nakamoto consensus, not of the blockchain data structure, but the combination of the two (or something that bears passing resemblance to that combination) is what usually gets called a "blockchain". Unfortunately this usage of the word is borderline useless because people keep loosening the requirements of the system so as to allow their harebrained setups to count as a "blockchain".
One way the problem can be unsolvable is not to be literally unsolvable but philosophically unsolvable, which is why bitcoin itself is probably a legitimately good application of the idea. The anarchic ideal is to not trust anyone in particular with controlling money, and any actor who says "no trust me, I'll do it right" is probably less trustworthy for having said that, so it seems unsolvable. So a 'self-organizing' coordination is somewhat necessary, essentially for the same reasons we like democracies more than autocracies.
(uh but proof of work is evil, so, just cause it's a good usecase doesn't mean it should exist.)
Besides that, most of the 'coordination problems' that people purport to want blockchains for seem to be simple cases of glaciation and incompetence. If you can't reconcile accounts across banks / supply chains / etc efficiently, your industry just sucks technologically and needs to get it together, and it'll still suck when you have a blockchain making your IT more expensive, but at least then you don't have to reach consensus on protocols so good for you I guess?
I would love to hear of other useful cases of otherwise-unsolvable coordination problems, but I really can't remember any right now.
On the other hand, ETH-like cases are completely legitimate uses of blockchain-like things ('running code in the ether' is not something you can do any other way, basically by definition, and is also just _cool_), but they are rather different and not directly comparable.
Let's say you get meat delivered by cooling trucks and this is mirrored in a public block chain. You publicly claim that all your meat is sufficiently cooled and every single delivery is tracked. If this data is in a public block chain, there is no doubt that you didn't input this data, it was in fact the delivery company, and if they cheated with their cooling sensors, the liability is on them. With a privately hosted database under control of the corporation (you), there would be suspicion that you manipulated it.
So it doesn't actually solve the problem, but you can legitimately claim that you did as much as you could (as far as using technology goes at least) to ensure the quality of the delivered meat.
So bitcoin solves the problem of not wanting governments being able to print extra money. The sibling comment [1] about timestamping the date of birth of veal is not a good use case, because it's perfectly possible and easier to set up a central authority that the veterinarian can report to. Which, according to a response [2], is exactly what happened, and solves the problem of timestamping veal just fine.
Cross parties or even industries may be a better target.
Op says it won't help authorship since earlier real author can claim he didn't use the blockchain but it's still helpful to prove something simply existed.
You find a security vulnerability in some applications. You want to make an anonymous disclosure but you want to be able to prove you knew about it at a certain time.
So you create the message "I John Doe has found the vulnerability ..." and add the hash to the blockchain.
You can now definitely prove that you knew about it and had documented it at a certain timestamp before the disclosure.
All a Blockchain is, is a public, append only database. That's it.
And no, it does not require "proof of work". People have released lots of Blockchains that do not have proof of work. They might even use a central authority to sign their blockchain transactions.
Public append only databases have existed for a long time, and are quite useful.
Someone else gave the example of git. Yes git is a Blockchain. Really.
There are a lot of reasons to use a public append only database, as opposed to a private database, hidden behind a central authority.
The veterinary that comes to check it posts a validation mark on the blockchain. If you trust the veterinary, you should trust the birthdate.
The veal grows up to become a cow, and is sent for slaughter. The farmer stores an event on the blockchain and sends it to be cut into meat.
The slaughterhouse stores an event (with the weight) on the blockchain and sends it for distribution.
The butcher creates the packets of meat, with a QR-code which lets you check the whole list of events, with their dates and places, and of course, you can check that the same part of beef doesn't end up in two different shops. You have complete traceability of your meat despite all the actors not knowing each-others.
That's the key issue: Bitcoin works, because Bitcoins are "born" on the blockchain.
Anytime you need to relate real-world concepts to the blockchain, you need trust again. As you said: "if you trust the veterinary".
The anti-double-spend features of blockchains is what matters after that: your cow cannot be sent to slaughterhouse 1 and 2 at the same time. Slaugher house cannot ship it to butcher A and butcher B. And it's fairly easy to check that the butcher doesn't sell it twice.
Though as I said in another comment, this can all be solved very easily if you give the DB hosting to the veterinary authorities, and very likely to be much cheaper too.
https://secure.services.defra.gov.uk/wps/portal/ctso/
Everything you describe can be solved, in a better and more efficient way, by non-blockchain technologies.
Shall I remind you of this: https://en.wikipedia.org/wiki/2013_horse_meat_scandal#UK_Inv...
The blockchain doesn't offer a technological solution that couldn't be done with a centralized authority (I particularly like the way passports rfid reading involves certificates signed by each country). But it offers means to achieve that even if nobody safe enough wants to host the bloody service.
Blockchain isn't going to solve that - you could put the ingredients in the on it and have them signed etc but at the end of the day humans are mixing the food.