Shake's interface takes a little getting used to, but your patience is rewarded.

Apple's Shake has long been an effects-compositing powerhouse - so good that it's regularly used to conjure up eye-popping scenes for movies such as The Lord of the Rings and Pirates of the Caribbean. But now, with version 4.1, Shake is no longer the tool that only fat-cat Hollywood effects shops can afford. Originally priced at $2,999, the new Shake (a Universal app, no less) now costs only $499 (OK, you can stop rubbing your eyes in disbelief). Shake is roughly half the price of competing compositors such as Adobe's After Effects 7 Pro Edition and Autodesk's Combustion 4. Shake's new, lean price makes it a nearly irresistible proposition - if you can see past a few quirks.

Shake has an impressive lineup of hardcore compositing tools. For starters, it offers two powerful keyers (keying is the act of removing an element of an image from its background), Keylight and Primatte, which can be used individually or together to minimize common keying headaches. Among many other things, Shake's keyers can pull a sharp key from a poorly lit green or blue screen, can successfully isolate frizzy hair, glass, and other hard-to-key elements, and can also remove green or blue tints that have spilled off a screen and onto your actors. Of course, you'll find similar tools in other compositors, but Shake delivers them at a lower price.

Shake also lets you composite 2D images in 3D space, creating a sense of depth between one element and another. It's easy to tag elements for 3D treatment, arrange them in 3D, and then move a virtual camera around the world (along with simulating camera-lens behaviors such as focal length and depth of field). You can't add 3D light sources and shadows (you can in After Effects and Combustion), but you can match camera moves created in 3D apps such as Maya.

You'll also find a full-fledged motion tracker, which, among other things, is handy for mapping an image onto another moving image (say, slapping an advertisement onto the side of a bus). An image stabilization feature called Smoothcam can take appreciable camera shake out of footage while keeping the final image remarkably sharp. Likewise, Shake uses optical-flow technology to smoothly speed up or slow down footage, or convert it to slow motion, with an image quality that seems on par with the best results found in high-end plug-ins for other compositors and is way ahead of what Final Cut Pro manages.