Im really pleased to announce the first public beta of Syphon, which lets various audio/video environments share video in realtime. We have implementations for Jitter, Quartz Composer, FreeFrameGL and Unity Pro, and know of some exciting announcements from commercial app developers who are integrating new products and designing products around Syphon.
Syphon for Jitter will allow you to push matrices and jit.gl.textures to any supported Syphon application, or receive textures from any Syphon server on your system. This means Jitter Unity, Quartz Composer hosts, FFGL hosts, and other apps and implementations as they become available.
Think of it as a send / receive pair across applications, for video, or 'soundflower' for video if you like.
Just to give an idea of performance, I am able to share 4K frames (jit.noise 1 4096 2048) to Quartz Composer and test applications (simultaneously) at over 40fps, on the GPU, on my laptop.