*Hopes that Cris doesn't use as many triangles in a sub-d mesh, as he did in the Sentinel*...hehehehe. Actually Biroboy, you can grab a cache script online that caches particle sims to disk rather than RAM for PFlow, and it auto-reads those files back in from HDD. Also realtime scrubbing with millions of particles in the scene is cool on it's own. This is what I do in Houdini, therefor freeing up lots of lovely ram for better suited tasks.
It's all about resource micro-management.
Huzzah for Sentinel re-vamp!