Hostile + Friendly NPC Modes, Ragdolling, Eye Posing. All free on Steam Workshop.
This Krystal cosplay hasn't debuted publicly yet, but you can check out lots of WIP photos from this painted bodysuit-based Krystal cosplay by Moonllita.
Another very photogenic human Krystal cosplayer appeared this year.
Tail physics and fur, but still a very work in progress rig.
Zyn of OxygenImpulse has made her Krystal charms available for customization and purchase.
Two more videos of Ayano cosplaying as Krystal at Further Confusion 2011. These are just little side moments that didn't make it into the final video.