Creating a distributed system that allows anyone to transact in any currency the wish to (fiat or digital) is the point of Stellar and Ripple.

I've been using Ripple since it launched; the distributed exchange capability is the killer feature.

All of the stuff happening with Ethereum, Counterparty, tree chains and side chains are efforts to add features to Bitcoin (and related) cryptocurrencies that already exist in Ripple and Stellar.

It's the glue between fiat and digital/cryptocurrencies.