I use blockchain to pay people to block phone spam.[1] It's also the subject of my patented algorithm on killing phone spam by requiring a refundable cash deposit for non-contacts phone calls. [2]
I wrote a short white paper on this theory too. [3]
How do you possibly have a patent on that. That's pretty much the oldest proposal for dealing with spam in existence. Bitcoin is even based on something called HashCash, which is roughly the same thing minus the refundability.
Yes, I took great inspiration from HashCash and Proof of Work in general.
Re: minus the refundability
The refundability is the main thing that allowed us to patent this. HashCash, and the large PoW required by Bitcoin are meant to strain any attempt to transact on the respective network. Ours only strains bad callers (monetarily) and does not strain good callers.
The argument we presented was that good/bad callers can be simplified as calls that lasts more/less than some time threshold.
Simple, user-friendly, intuitive, and serves the purpose of disincentivizing high volume spam calls while giving legit unknown callers a chance to bypass the blind filter.
That's cool that it works. So that's one solution to that problem.
Here in France, phone spam is essentially non-existant, and I'm nearly sure there are no block chains involved.
I'd posit that this is a tech workaround for a political problem. Which is fine in my book, but it's not exactly a killer application for the technology that is block chain, if really you'd want (and could have) something that does the job better.
Yes, it's a bigger problem in these countries, [1] potentially because of the use of multi-country languages spoken by massive numbers of people.
Re: if really you'd want (and could have) something that does the job better.
I'd argue that nothing is better than blockchain in terms of dealing with monetary policy in each country. Since this solution is 100% targeted at the economic incentives that drive phone spam, the reward must be a financial incentive that is easy to globally implement and furthermore allow a user to easily transact with, regardless of country. P2P currencies means someone else in whatever country can worry about designing services that take/use Nano, while I focus on blocking phone spam and don't get wrapped up in potential race/optimization conditions in using "funny money". /rant
Doesn't mean this is a killer app, just as you said, 1 way of trying to solve this 30 year old problem that will only get worse over time as the Internet of Things matures.