Simple: Put one of the 1.0.4 Hellracks on your Scoundrel follower and train his multishot. He will deal more DPS than I've seen scoundrel ever do because of the 5k-10k hellrack proc, and he will occasionally ROOT THEM IN PLACE, it's really cool on big monster packs when he aoe roots.
There is no animation for the root effect, the enemies are simply are immobilized.