This is another blender particle experiment. This time I used some flock particles that try to fly towards an empty and have to choose a path around a cube. I don't render the particles themselve but use a path renderer to simulate some growing plants.
I've set the rendering of the particles to b-spline, baked the pyhsics simulation (under chache) and then animated the end value of the bspline.
you can download the blend file here
AN experiment - force field curl clusters
twisted torus particles
particle density volumetric material