Image Magick - tools and libraries to read, write, and manipulate an image in any of the more popular image formats - Linux, Unix, Windows 95/NT, OS/2, Mac ...
GIF Animation Tools - for Windows
3D Styler - for Windows
POV is a powerful 3d rendering engine- for DOS, Windows 95/98/NT, Linux, Unix, Mac....
Audio/Video
For RedHat Linux
Free Basic RealSlideShow - combine digital images with narration and music to make slide shows for the Web.
Free Basic RealProducer - converts your audio and video files—or live feeds—into RealAudio and RealVideo for the Internet or your intranet.
Free Basic RealPresenter - turns Microsoft PowerPoint slides or Web pages into Web presentations for your workgroup.
Free Basic RealServerbroadcast your streaming media content over the Web, to be seen and heard in the RealPlayer.
For other OS
Free Basic RealSlideShow
Free Basic RealProducer
Free Basic RealPresenter
Free Basic RealServer
Miscellaneous