Converting Videos
Any Video Converter
http://www.any-video-converter.com/products/for_video_free/
Any Video Converter has a simple, easy-to-use graphical interface to convert between popular video formats. Any Video Converter is especially useful for converting downloaded FLVs of YouTube videos into a more usable format.
Handbrake
http://handbrake.fr/
"HandBrake is an open-source, GPL-licensed, multiplatform, multithreaded video transcoder, available for MacOS X, Linux and Windows."
Free Video Cutter
http://www.freevideocutter.com/
"Free Video Cutter is a free video utility to help you to cut and split your video files into small size you can use it as a video cutter, video splitter or video clipper".
iDesktop.tv
http://www.idesktop.tv/
"iDesktop.tv is an incredibly cool dynamic web 2.0 application, with a terrific modern design, that brings you a better way to search and watch YouTube videos. "