Jahshaka
Adding effects, creating custom keying, layering backgrounds and building your own animated sequences in video typically requires both creative talent and expensive editing packages. While there's no software in the world capable of eliminating the need for creative talent, Jahshaka does a great job replacing the need for the pricy tools required for typical special effects rendering projects. This doesn't mean people already comfortable with working in environments where video keying, animation design and video coloring are going to abandon their current toolset. Jahshaka brings the rest of us access to these features without needing to mortage our lives to have the necessary tools. Non-linear video editing is currently available only to Linux users, but the rest of the feature set, including video paint, keying, color correction, 2d and 3d effects and a system for sharing files privately across a network are available for Windows, Linux and OS X. [Windows 2k/XP Mac OS X $0.00]
Thanks to Markus for reminding me I'd never featured this.