iShowU is software to capture and record video from your screen into a Quicktime movie in real-time. Create tutorials, make a demo for the Web, record your favorite game, collaborate on UI design, or show tech support what's really going on with that broken program. It allows you to capture and record anything you can see on your screen, along with audio from any compatible source.
LiVES is a simple to use yet powerful video effects, editing, conversion, and playback system aimed at the digital video artist and VJ. It runs under Linux, BSD, Mac OS X/Darwin, IRIX, and openMosix. It is frame and sample accurate, can handle almost all types of video, and is fully extendable through plugins and the included plugin builder tool. It can also be controlled remotely using OSC.