After seeing this walkthrough (vimeo.com/11005057) over an interactive Fracture System on 3D Max I thought about trying to replicate the functionality in Cinema. With a little bit of xpresso, iterated ray collisions and some vector magic I was able to come up with exactly the same behaviour.
There are two other ways to have almost the same behaviour, the first one is utilizing the Clamp function on the Constraint Tag. But with 1000s of pieces it is really slow and has some hickups. The second one is to use rigid body dynamics with an high follow Position/Rotation value which can also slow down significantly with higher Pieces number. Also controlling the dynamics can be quite tricky.
BEWARE: It is really important that your fractured geometry pieces have their axis on the same Y value as otherwise your pieces won't be aligned and positioned correctly.
(no audio & wild mouse behaviour)