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.
XdTV is a program to watch, record, and stream TV. It interacts with AleVT (Teletext) and Nxtvepg (NextView) and supports the bttv, bktr, and dvb APIs. It contains some deinterlacing filters and records video files with various containers (AVI, MPEG, Ogg, etc.) and many codecs: FFMpeg >=0.4.6, XviD 0.9 and 1.x, DivX 4 and 5, and Vorbis/Theora >=1.0a5. It has some plugin capabilities.
gtk-screenshot is a program for taking screenshots. It captures the screen or a window and saves the image in the PNG format. It is similar to gnome-screenshot but it's not a GNOME application. All parameters may be specified on the command line, or the application can be graphicaly driven.