I was wondering what you felt was the greatest submission hold of all time. Not necessarily most effective, but just what you consider the best. For example, I think the sleeper hold (if that counts) and the figure four are probably the most well known and iconic, but my personal favorite submission ever is the cross face chicken wing. It doesn't look like much but I know from high school wrestling that chicken wings can be VERY painful if done correctly, thus I always smile when I see it done in any capacity in pro wrestling.
I hope I'm not being stereotypical here but given your known admiration for Bret and Owen Hart I'm guessing the Sharpshooter has to be near the top of your list right?
Gonna have to go with the cobra sleeper, which is more effective than the regular one by tying up the guy’s arm and making it tougher to escape. Simple and effective.