Little scenario:

Pretend its the 3rd century BC and you are a Roman legionaire on the field of battle. As you advance, you happen to notice a number of really pissed off, armored elephants charging right at you. What do you do?

I know what I would do. And it wouldn't be stand there :)

On a serious note, I wonder how well they trample. I suppose when you are talking about thousands and thousands of men (and plenty of elephants to boot), there's just no where to run.

I wonder if a rampaging herd of wild turtles would have a similiar effect...