There are two brushes in this set of Tool Presets. They both lay down a swath of dots with hues that vary slightly from the chosen color. They build up really nicely and I recommend layering them up with variations on color for some really nice effects.
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Here are a couple style frames I made for a project a couple years ago. Alas, I ended up not using the effect because the brushes were too difficult to animate, but I think the frames sure came out nice.
Please take a look at the blog sidebar for instructions on installing them. Enjoy!
Download Watery Bubble Brushes Here
Edit: If anyone is interested in seeing the film that the above style frames were taken from, visit Coalition of the Willing, a film that discusses how we can use new internet technologies to leverage the powers of activists, experts, and ordinary citizens in collaborative ventures to combat climate change. I designed and directed a segment on the 60's.