I was a pax on board an Alouette III recently and experienced loss of tail rotor command first hand. The solution to getting us to the ground safely seemed to be a combination of a few of the last posts.
Immediately the problem occured (just after take off from a clearing amongst some cocnut palms) the pilot elected to head back towards the nearest airfield (a virtually unmanned third world scrape in the jungle), a journey which took an agonising 40 minutes.
His approach was long and low, progressively easing off the speed as we got closer to the field, allowing him time to assess the degree of control. We had the benefit of about a 20kt head wind which meant that he was then able to bring us almost into the hover.
So as the yaw started to kick in and the outside world started to rotate he executed what one might term a "positive" landing. The Alouette was equipped with wheels but the pilot chose to land in the long grass off the runway which seemed to help in absorbing the impact of our landing. The outcome however was that we all emerged unscathed (and the a/c was easily repairable).
Hats off to our pilot, he handled it extremely calmly and I really hope that I get the chance to fly with him again. Unfortunately we had to abandon the heli and switch to fixed wing to complete our task. And the cause..., a failure of the t/r command cable.