Interactive smoke and fog, dollar bills that flutter across the floor, enhanced rain that beads off Batman's cape -- that's right, it's NVIDIA's obligatory "look-how-good-Batman-looks-on-our-hardware" video for Arkham Knight!
While I've never caught myself playing an Arkham game on a console or AMD-powered PC and lamenting the lack of fluttering debris, I am a big fan of smoke that moves like smoke and rain that acts like rain. These are things that NVIDIA's GameWorks technology can do for you. The people watching your "Let's Play" video will appreciate the extra attention to detail, probably.
For comparison's sake, here's Batman: Arkham Knight running without GameWorks:
I can't wait to turn these features off so the game runs smoother on my computer when it drops on 23 June.