Coins that support smart contracts show that "cryptocurrency" isn't a great term. Even if you never try to use ether as a currency (and indeed, most people don't), Ethereum can and does still do lots of things completely unrelated to finance in any way, with ether just serving as computational fuel.
The interesting part is fully trustless peer-to-peer networks, not e-currencies. E-currencies are just an example of one thing you can run atop such a network protocol. They've already existed to some extent for a long time via protocols like BitTorrent, and these just expand on those ideas.