Paul Vunak has a "kit" on Killer Instinct training that is worth a look. I think it is a book and audio tape; there may be more there too, but I forget now.
I've been to a couple of Jeet Kune Do seminars (not with Paul, but with certified instructors who have trained with Paul) where we did soem of the Killer Instinct stuff. I can honestly say that the Killer Instinct material has penetrated every aspect of my training. I think this si so because it is so primal, and so effective. Vunak's program tells you that everyone has the Bad Man inside of them, and you can train yourself to let him out, and put him back too, when needed.
We were told to think of a fight like a scale of 1 to 10. You want to keep yourself at a level that allows you to survive until an opening happens. So, you may be at a 4 (of aggression, anger, etc.) and I may need to kick myself up to 2 or 3. You may pugh hard, up to a 6 , and I will need to kick things up to a level that allows me to deal with things. Then the magic happens when that opening occurs. Openings, or interceptions, occur when the opponent stumbles, after you have finger jabbed them in the eye and they "flinch", after your fast snap kick to their balls has struck home, or whatever. Once you get that opening, BAM! Kick it to 10, RUN down their throats and feed elbows, head butts, etc.
One drill we would do is start at the end of a room facing a partner. Line A would straight blast (series of rapid punches done on the run in order to get to the neck) whiel line B would back pedal as fast as they could to avoid getting hit. If they get hit, they lose. The instructor would bang rattan sticks together as a que for line A to kick it to 10 and BLAST down their throats. We would stop at the half-way mark of the hall if no punches scored home. Then we shortened the distance and repeated. And repeated. And we did it until we were allowed to take only one step. As the distance was shortened, that fire inside actually would burn hotter once the sticks were banged together. I can still remember just beign fixated on my partner's neck, I wanted to eat it for lunch. BANG woudl go the sticks and I'd launch out yelling. Ahh... that's good training!
Anyways, that is just some idea of my dances with the Bad Man. Check out VUnak's Killer Instinct stuff if you want more. or bug Mick and Duane! Bug them enough and you may see the Bad Man!
I hope this helps.