For those who have limited budgets to work on their indie game projects (non-commercial of course) betas or demos (this project is currently and legally just a demonstration one) may not have the budget to learn modeling and game animation using fullblown packages like Maya or 3D Studio Max.
I spent a couple years each using XSI and Maya (been meaning to do Max but never got around to it). I did a few commercial projects and a few private “tests” of different things (primarily the characters and buildings I want to use in the project)
The XSI Mod Tool has the ability to export in FBX format as well as Collada and Unreal. It is free for noncommercial projects. For students or artists simply trying to do projects and learn (perhaps to move into the industry), they make a good match.
PhysX is built into the full version of XSI (I have no idea about Modtool inclusion).
For those familiar with Torque (low-cost engine, one of the first with paged/paging terrain system), there is also a plugin for the Modtool for that engine.
An excellent tutorial for XSI Modtool and that engine is linked here