My mare does that with me. I had an incredible experience a few weeks ago where my mare put herself between me and 2 playing foals. As it happened to be one of the foals stumbled down. If it hadnt been for her clearly putting herself next to me I would have been trampled which at the time would have not been a good thing as I was on crutches.
Ok ok, the first one has defanaitly gotta be up there. But with all the others, I never knew horses could be so mean! Lol, kidding. You guys must have the camera out at the right time eh? I'll try and get a funny but mean picture soon. The one that is just above, LOOKS hilarious!!!