PIVX is a good cryptoucurrency which has grown a lot in the past months. It still has more to grow though.
There is one good project for a privacy coin with a big potential which will start seeing the light next month after a coin swap due a fork from PIVX.
It's POSW now, future STAKENET with masternodes, cold storage, it's supported by Ledger Nano S and it will give a service to stake other POS coins.. I could be huge!
https://steemit.com/cryptocurrency/@greensmile/posw-stakenet-2018-roadmap