Photoshop brushes are one of the most useful and often under-rated aspects of the program. Download these Free Photoshop Brushes and upload them to Photoshop. Free original Photoshop brushes for web & graphic designers!

Avid Free DV (Geedie says XP only): Avid Free DV is simply a streamlined version of Avid’s professional video editing software and has many limited capabilities. Once you’ve had a chance to familiarize yourself with the Avid editing interface we recommend upgrading to Avid Xpress DV or Avid Xpress Pro where you will benefit dramatically with increased functionality and power.
http://www.avid.com/freedv/features.asp

AVE Visual Editor: enables user without any programming experience to use the power of AviSynth. With AVE Visual Editor you simply connect icons with lines and when graph is complete watch the output.
http://www.avisynth.org/vion11/aveguide.html

AviTricks: is a non-linear, non-destructive AVI video editor with real-time preview. It makes cutting and joining footage easy and includes a wide range of built-in adjustable effects that can be used separately or in combination. The AviTricks Video Editor is still in production.
http://www.bobyte.com/

Cinelerra (Linux only): Unlike most of the Linux solutions out there, Cinelerra requires no emulation of proprietary operating systems, no commercial add-ons, no banner advertizements, no corporate dependancies, no terrorists, just a boring old Linux box.
http://heroinewarrior.com/cinelerra.php3

DDClip (not free anymore, but some budget light versions on the site): is a professional, non-linear, non-destructive, multitrack, real-time audio and video editor for Windows. It allows you to process and mix up to 32 high-quality audio tracks (24 bit/96 kHz is available) with real-time audio effects (including any DirectX plug-ins) on PC with any Windows-compatible sound card.
http://www.softlab-nsk.com/ddclipro/index.html

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. Edit with flexibility and speed, create effects in real time, animate with unlimited features, paint and design on moving video, create music with all the tools the pros use, work in any format at any resolution and more.
http://www.jahshaka.org/

Videocharge: VideoCharge is a multifunction, easy in use software product for conversion of Video, Audio, or Image files sequences!
http://www.videocharge.com/

Virtualdub: VirtualDub is a video capture/processing utility for 32-bit Windows platforms (95/98/ME/NT4/2000/XP), licensed under the GNU General Public License (GPL). It lacks the editing power of a general-purpose editor such as Adobe Premiere, but is streamlined for fast linear operations over video.
http://www.virtualdub.org/

Wax: is a high performance and flexible video compositing and special effects software. The idea for Wax is to be very general purpose and flexible in video compositing and effects, so that you can compose your dream video sequence with ease everytime.
http://www.debugmode.com/wax/