This 2D fluid simulator is the first of its kind (written in metal using research papers Chirag linked on his website) and the example video is charming yet grotesque at the same time. Very engaging content.
CARL stands for Code Augmented Reality Live. In an algorave (algorithmic rave), a programmer/performer codes a 3D environment on the fly using a raymarching algorithm in GLSL; that shader code is also executing and updating on everyone's phone in real time. Using phone orientation and audio input, CARL is a window into an immersive and evolving 3D algorithmic world that dances to the music.
You can read more about CARL here: http://Charstiles.com/carl
PsychOut lets you write and edit Metal shaders and see the results in real time.