Check out Adrià Navarro’s Processing-powered Inkscapes project. The Verge writes,

“Inkscapes” is a sprawling installation that turns tablet doodling into something more profound. Created by Adrià Navarro and DI Shin, the system streams live iPad drawings across a giant, 120-foot-long display, located inside New York’s InterActive Corps building. The result is a hypnotic, undulating mural that’s equal parts painting and performance.

[Previously: Collaborative drawing: Is there a “there” there?]
If Inkscapes is up your alley, see also Fluidic. Colossal writes,

The interactive light sculpture is made from 12,000 suspended spheres that act as three dimensional pixels, or voxels. Surrounded by 3D cameras the piece can sense viewer’s motions which are then translated into light patterns, but amazingly the light supplied to the individual voxels is fully external. An array of high-speed lasers project into the cloud to create the dynamic visuals in real-time.