Shadertoy - Build shaders, share them, and learn from the best community.
Gravity Free - Gravity Free – Light Particles Manipulation App developed and published by Kfirapps Limited.
KodeLife - Real-time GPU shader editor, live-code performance tool and graphics prototyping sketchpad.
Particlescape - Particlescape app lets you create stunning patterns at your fingertips.
SHADERed - Lightweight, full-featured desktop tool for creating and testing HLSL and GLSL shaders
Flasia - Flasia is a highly complex and interactive visualizer yet it also a beautiful work of art.