One of the earliest digital coins, Peercoin (PPC) was released in 2012. It was the first to bring the “Proof-of-Stake” concept to life. Peercoin is a peer-to-peer cryptocurrency and is minable. PPC is widely represented on exchanges. You can also buy this coin for fiat currency.
Power Ledger (POWR) is an ERC-20 compliant market token of the energy platform, that is listed by a number of exchanges. It can also be traded against the fiat currency on some of these platforms: for example, against USD on the LocalTrade exchange.
Storm (STORM) is an ERC-20 fuel token of the eponymous platform, which works as the freelancer marketplace. The token is listed by a number of exchanges.