Is there any way to have particles pile up on each other? I'd like to be able to fill up a container, but even if I have the particles push each other, they won't lay on top of one another; they'll just settle down at the bottom and overlap. I'm guessing Carrara doesn't treat them as instances.
I'm using C5 by the way.

Hi TM, Particles only exist as a Hot Point, not an actual mesh. They are really non-dimensional. So, no, you can't make them accumulate. The Metaballs option can fake fluids until you start dealing with issues of accumulation. Blender is free and has a pretty good fluid solver/generator if you want to give it a try. www.blender.org - for the program. They've got some good tutorials on the site. Also, for additional Blender info, this site is good - http://www.blenderunderground.com/ Blender's interface is, um, unique. Takes awhile to get your head around - at least it did for me - but a cool program. I have brought fluids via sequential .obj export into Carrara from Blender but it takes awhile to make them look decent because it's a frame-by-frame adjustment process in the Vertex modeler. Blender has a decent renderer but it doesn't let you work with the other Carrara capabilities you've come to know and love. ;-)

Thank, Mark! I remember checking out Blender a couple years ago when I was first starting out, but found it too daunting. I think I'll give it another try.