I've been playing Half Life 2 lately on my 360 and have been pretty impressed with the physics engine, but this was so amazing I had to take a picture.  I shot this poor fellow from a mile away using the telescopic scope on the crossbow.  When I finally made my way across to his location I was amazed to find that the crossbow arrow had gone through him and lodged into the bridges scaffold work pinning him up of the ground.  Impressive stuff!