Have you seen the Grantcoin Manna concept (short post with a couple of links - https://steemit.com/basicincome/@revo/grantcoin-universal-basic-income)? They are implementing a UBI via cryptocoin. I'm keen to follow along with this one and see how it goes (i'll eventually sign up to it myself, I guess). I can't help thinking that the consensus/popular view of economics and monetary systems is arse-about. This idea that money flows from economic activity, when it is actually money in the first place that defines economic activity. It's actually a self-perpetuating system, as far as I can see. Yet this is one of the criticisms people make of cryptocurrencies. It seems to me that what Grantcoin is doing (literally creating money to meet a need) is no different to how regular fiat money systems work. And a Grantcoin-like system seems to me to be less potentially ponzi-ish than the regular monetary system, because it doesn't generate ever growing debt in its production. The regular monetary system we run now can never repay world debt (without governments either cancelling it, or just printing an amount of money equal to that debt and then repaying it), as the interest charges on debt mean that more money needs to be created to meet the debt obligations.

(edit: sorry, I see now your post mentions Grantcoin)