I might be biased
ok, I am biased, but:
NXT and SuperNET.
NXT has produced so much useful tech (including much of SuperNET) and has just passed the one year live mark. That's a whole year of constant attack but the NXT core and blockchain are still solid and stable.
NXT is also one of the straightest and most trustworthy crypto projects: the NXT community and stakeholders have proved over the last year that they will make hard decisions to maintain the integrity of NXT, and that these decisions come from the community....not from superstar/prima donna/scammer devs.
Did I mention the open-source and decentralisation yet?
For SuperNET, check out the client:
https://nxtforum.org/lite-multigateway-releases/supernet-v1-3-4-3/This client represents, I guess, about 20% of currently planned SuperNet functionality, maybe less.
So it's not just a collection of assets, but a fully operational battle station.....