What is CrowdFX? It's a dedicated environment for building sophisticated crowd simulations in Softimage. Built on ICE, you can create complex effects with large numbers of characters that react intelligently to their environment and each other. And because it's ICE, you can use all the standard ICE nodes and compounds to customize the simulation as you like, in addition to using the special CrowdFX ICE nodes and compounds.
CrowdFX is basically a point cloud-based ICE simulation. You choose one or more characters whose envelope geometries are instanced on each particle in the simulated point cloud. Although similar in some ways to regular ICE particle instances, CrowdFX is different because you can blend each character's animation sources in the simulation. You can even constrain parts of the character's rig to modify the animation within the simulation.
CrowdFX also allows you to modify the behavior of the actors to simulate intelligent collision avoidance with other actors, as well as obstacles (called walls). You can also make the actors move toward goals that you create, or follow a path.
While you might think that you can use only bipeds as the characters in a crowd, CrowdFX is designed for any type of rigged enveloped mesh in a model that has action sources. This can be a biped, quadruped, or any type of organism or object that you want to exhibit crowd behavior. Its rig can have any type of hierarchy made up of either nulls or bones, and have a polygon mesh assigned as its envelope. Once a character is in CrowdFX, it's known as an actor.
One of the things that you usually want in a crowd is variation. You can do this in any number of ways in CrowdFX, from different source characters you use in the simulation to modifying the envelope geometry with different shape keys, using different materials and textures, or randomly changing the actor's size in the simulation.
Once you've finished a crowd simulation, you can export it in the familiar FBX format to send to Autodesk® Maya® and other 3D programs that can import FBX.
Quick Start on Creating a Crowd
You can quickly create a crowd simulation for learning and testing by doing these two steps:
Choose the CrowdFX 
Actors Get Actor Default Pedestrian command on the ICE toolbar.
This loads a low-resolution polygon mesh rigged character with several actions already set up for you to use.
Choose the CrowdFX Simulation Create Pedestrian or Stadium command to create the simulation using a default particle emitter.
Then follow the steps in Overview of the CrowdFX Workflow to get a sense of the different elements that are involved in creating a CrowdFX simulation.
Loading the CrowdFX Sample Scenes
When you're ready to start exploring what can be done with CrowdFX, or need a good base for your own crowd simulation, check out the sample scenes that are shipped with Softimage.
Load a sample scene from the \Data\XSI_Samples\Scenes\ICE folder in your Softimage installation directory. All CrowdFX scenes have a CrowdFX_ prefix.
You can quickly open this folder by choosing User Tools Browse Examples from the toolbar in the ICE Tree view.
