In one of the levels, there is a part where if you so desire, you can kick a Mook off a scaffolding and watch him tumble down. You can do whatever, high jump kick, low sweep, low blow. If you go for a high jump kick (Press LB, then RT) and he moves, you'll go flying off instead.
There are multiple locations, especially in chapters 6 and 8, where you can knock pursuit cops off buildings. Particularly hilarious, if a pursuit cop is standing with his back to the edge of a building, he may still do a backflip, thereby killing himself.