The After Effects: Effects A-Z tip series from Motionworks continues with guest host James Zwadlo on the CC Bubbles effect that ships with After Effects.
As James points out, this filter is simpler than the Foam filter in AE, and that can make for effective control despite limitations. He shows to to get a variety of looks, including one similar to Harry Franks’ Rippling Circles that uses Ball Action. Bubbles can be created with a number of other particle and faux particle systems, and Mylenium offers a few free projects with different approaches.