Ok, this works for movies as well, but here is a good free software for adding special effects to animations and movies. It's no substitute for paid ones, but if you can't afford the professional compositing software, this one is the only decent free one out there. Its kinda hard to learn at first, but eventually you can get the hang of it. So far, in all of my animations that have special effects (including my logo with the cannon firing) I have used it. It is WAX 2.0, and here is it's website: http://www.debugmode.com/wax/
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