At the gym the other day, a guy showed me a crazy-effective choke; he grabbed my arm and put it around my own nack and pulled forward and created a lock on the side opposite my hand...he hadn't finished locking and I could already feel the choke a little, he finally locked and then closed the choke and I tapped in about 2 seconds. I am trying to find it, it was extrememely powerful and it seems very easy to setup.

As I have done Karate, I know what you mean, I'm not trying to bash Karate, but in my experience, we did'nt spar or use and of the techniques in lifelike situations, some may have worked, but we seemed to concentrate on form and katas and stuff; I may still have done Karate, but I find MMA especially the grappling is more suited to my 5'7" 140lbs body.