Look at the CC filter that ship with AE, particularly Blobbylize and Mr. Mercury.

Dean Velez has projects for sale that use these to great effect: <http://motiongraphicslab.com/ani-elements/liquid-element-10.html>

Jonas_Hummelstrand@adobeforums.com wrote:
> Look at the CC filter that ship with AE, particularly Blobbylize and Mr. Mercury.
>
> Dean Velez has projects for sale that use these to great effect: <http://motiongraphicslab.com/ani-elements/liquid-element-10.html>

Considering the time you would put into tweaking about with filters that
are not specific to the effect you want, I have to agree with Mylenium.
Take a piece of cardboard, a dishpan and a glass of water. Pour and
shoot.