I've heard of the term, but from what I understand, no actual working implementation of that concept currently exists, right?
Decred is currently mined using a mix of PoW and PoS.
Current supply[1]:
PoW-mined: 43.5% PoS-mined: 21.8% Development Subsidy: 7.3% Airdrop: 13.7% Dev Premine: 13.7%
Blackcoin is also PoS mined, and NXT reaches consensus using PoS but if IIUC is not mined per se.
Look into Proof of Stake (PoS) - people are looking into more efficient blockchains (although there's some controversy over whether it will work)