Avidemux

Avidemux is a free video editor designed for simple cutting, filtering and encoding tasks. It supports many file types, including AVI, DVD compatible MPEG files, MP4 and ASF, using a variety of codecs. Tasks can be automated using projects, job queue and powerful scripting capabilities.

Linux
Windows
Mac OSX
Jahshaka

JAHSHAKA is the worlds first OpenSource Realtime Editing and Effects System. Jahshaka takes advantage of the power of OpenGL and OpenML to give its users exceptional levels of performance. We currently support Linux, OsX, Irix and Windows, and Solaris is on the way! Jahshaka is licenced to the public under the GNU GPL agreement.

Linux
Windows
Mac OSX