TP Partio - Cinema 4D
http://aescripts.com/tp-partio/
TP Partio is a plugin for Cinema 4D that will let you cache Thinking Particle particles, write them to disk, share them with other applications and read them back. It will let you take a snapshot of a current frame of your simulation and let it continue from there. It'll let you play your sims backwards, while you can scrub through them on your timeline.