Whether you're of an Anymation philosophy or not, sometimes a special effect you're looking to pull off is best served by compositing rather than by trying to accomplish it within your engine. And there is no better nor more affordable source for this chroma-ready effects footage than Detonation Films. Whether your needs be violent (blood, explosions, carnage, etc.) or non-violent (rain, snow, etc.), you'll find some amazing footage here, all primed and composite-ready.

They give away a significant number of items for free, and even their HD resolution stuff is reasonably priced compared to larger commercial stock footage outlets. These guys' target audience is definitely the indie filmmaker, but the quality is superb and professional.

It's one of those finds that I almost hesitate to share before I've had opportunity to wow someone with it in my own films... but it's just too good to keep quiet.

Check out their email list, which keeps you posted on all new releases and also entitles you to some freebies you can't get anywhere else.