Inyati, When they're feeling peaceful, they really are a symbol of peace and contentment... Laying down, eyes closed, chewing cud... when you get them mad, they may as well be a pack of sled dogs.
I wish I knew more about training.. I have some that I think could be good at doing tricks, or pulling carts... Heck there was a girl who's parents didn't allow to have a horse, so she stated doing DRESSAGE on a cow... There's a ranch in texas somewhere, and they have riding longhorns, and herd cattle, on cattle.
I'm probably not the only person you know who'd film the udder scratches.. I just beat Inyati to it!