I know there's only one feature added with this mod, but it's still pretty cool on its own, and I'm thinking of adding on to it. I had this idea when I was messing around with player heads. I decided to make a mob with similar properties to the player head, in the sense that it takes on the skin of the given player.
You can name them like you would any other mob, and that name will determine what player they look like.
You can befriend them by throwing a diamond at them. This also gives you the "Diamonds to you!" achievement, if you are at the appropriate progress level.
They will attack hostile mobs if holding a sword. They also do this if you haven't befriended them yet, regardless of the weapon. (You can't see it, but Notch is holding a diamond sword.)
I had to. You know I had to.
Got a suggestion? I'm all ears. Post any suggestions (yes, any) in the comments below. Maybe certain names drop certain objects? Maybe certain names make changes to the AI? Whatever your suggestion is, don't hesitate to post. Nothing (and I mean nothing) is too ridiculous.