...and effective, very effective. There's no guy I know - except myself - who didn't scream out in pain after I pushed it only a little backwards.
I never had to go as far as to actually break the finger though. But in normal logica, the bone in the finger should break when it is pushed backwards. If it doesn't break then, turning it left or right, it should do the trick. If it still doesn't word, then I can do only one more thing to ensure it breaks, but I am not so sure if it can heal anymore afterwards.
You see... I became quite famous for three straight years because of three movements.
1. I could (not anymore flat, mind you) lay my fingers flat on the back of my hand.
2. I could (still can, it became a normal movement) dislocate my thumb at any time.
3. I could, no, I can bend my arm around one, or two more times more than the average person.
I said I would like to make a screen shot of them, but except for the thing with my thumb, I need both hands to do it, and I have nothing left to make the screen shot