it lets you select any non-joint bodypart, use /setforce [value] to determine force, and press N to apply force to that bodypart in whatever direction your camera is pointed.
I've been gone for too long, but I'm going to try to do some sp stuff since it's hard (for me) to get players to play with me in mp (I'm a lonely ass nigga).
I hope you enjoy it though. They are rather spread apart in terms of when I made them. I haven't consistently played or done realism, so disregard the gameplay at least a bit.