I  know of Mysterium but the project never rely gained any traction, was able to raise huge amount of money in the ICO boom of 2017, recently Tachyon Protocol is making moves to make waves in the space  but the issue I see is getting users to their network, if they can they this would be huge for them, another thing is speed, if their network is not slow as compared to the centralized VPN it would be a good selling point