I'm at 0% and will stay that way until some government picks up such a blockchain currency and at least 10% of the entire population starts using it. At that point, I might buy into theirs.
Back in 2004, there was something called
Liberty Dollars, which looked like a pretty cool idea. You could exchange regular dollars for silver coins denominated in USD and spend them like normal coins. If the USD inflated, the liberty dollars would be revaluated automagically. There was some simple algorithm for this. Recall that silver has traded all the way up to $40+/oz within the past decade.
Unfortunately, the idea was so good that the feds went after the founder and locked him him. The coins looked at bit too much like the official ones in form or function.
I also recall as the virtual gold sites.
So even if it sounded like a great idea, I'm glad I moved too slow to actually buy into it. It would have been a pain in the ass to be left holding the bag on something that's ultimately challenging a very profitable government "business". There's any number of ways they can make your financial life miserable via tax-reporting laws. Therefore I prefer to keep it simple.