In the room after you fight the strange creature that mimics your moves, there should be three horizontal crushers on both sides. Go to the side where the floor hasn't collapsed and pull the lever on that side (just to get the checkpoint). Take out a gun and wait for the crushers to go back in. Then, run and jump into the path of the crusher when it comes back out with the weapon still out. If timed correctly, the impact will throw you into the ceiling with surprising results. Note: This may be somewhat difficult to do.