Linker Animation Stand Personal Edition
Animation Stand is the leader in cross-platform tools for professional, cost effective, easy to use computer-assisted 2 1/2D character animation, compositing and film quality special effects. Other key features of Animation Stand include, multiplane camera control, automatic cel painting, 3-D shading, audio editing, production cost reporting, and easy output to film, HDTV, video, QuickTime, and standard graphics files. It's the only animation system with versions for all major platforms: Mac, SGI, and Windows (95, 98, NT, and 2000). Versions of Animation Stand can be intermixed, and all hot-link together to provide a seamless workgroup environment. Since 1989, professional and industrial animation studios, postproduction, and video facilities have used Animation Stand, worldwide. The Personal Edition, limited to a 256 x 192 pixel resolution, is a free download from Linker Systems' web site, and is aimed at those wishing to learn animation and special effects, or for producing small multimedia and web animations.

MonkeyJam
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Tapptoons Linetester
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Michael Purcell Storyboarder
This program makes it easy to create storyboards with camera info and scripting. Also, Storyboarder lets you keep track of what you have done in each scene.