minding your own business, when suddenly, a huge, fast moving man comes at you running at full steam, frothing at the mouth yelling "I'm going to kill you!" You have no time to run, no time to hide, no time to pull out a gun, no time to do anything except react FAST or get slammed into by this seemingly insane or drug crazy behemoth baring down on you fast! What do you do? Do you side step him, perhaps trip him, use his force against him, let physics or gravity do the rest and watch him slam into the ground and than go the opposite direction of him FAST. Or do you hit him with some nifty blow into just the right nerve cluster and watch him collapse to your immense relief. Do you grab him and pull him down and put him in some BJJ hold that not even the Gracies could break out of. Or do you do something else. All opinions appreciated.
Sorry, Joab, this is not a reasonable scenario to be answered. You have put forth a situation where you see an attack coming, but then you have our options limited due to lack of time? Then you want us to give you our response to the attack? I'm afraid that cannot be done. The best you can hope to get from us here is a thought-out answer based on experience and training, but that is by no means a real answer. In the situation you propose, there is no time to "think things out". The only answer is to experience it and find out (as previously stated).
There is simply not enough information to give a realistic answer, all we have is a big guy charging at us... how are their arms? How far away are they? Are they coming in looking like they are going to grab, hit, or ram with their shoulder? How much room do you have to move? If I can't draw and shoot (far less likely here in Australia, in any case), do I have other weapons? Does he? Does he have friends? Do I? Are there witnesses? What are the surroundings? Are there buildings, or cars? Can you see where I'm going with this?
The only thing I can say is that our tactics dictate a certain type of response, as for the particular application of technique, well, who knows? The sad fact of these type of hypothetical "What if?" questions is that they often belie a deeper issue, which is one of fear. This is in and of itself not a bad thing, as fear and greed are probably the best motivators that exist (just watch any advertising for that), and can generate new ideas and concepts to deal with changing conditions. The problem comes in when you start focusing on these scary scenarios over gaining an understanding of the tactics and principles of your chosen art.
By training the principles, you will find that you won't have the exact answer for every exact situation, but you will have a guide, or template, which you can adapt ot fit each and every situation. If you focus on individual situations (as here), all you are really doing is limiting your understanding and wasting energy on the unpreparable and unknowable. Your ability to handle such frightening scenarios (to you, others may have other things that scare them) will come not from spending time and energy thinking about them. That will just leave you scared, not improve your confidence at handling yourself (which is what you will actually need). I don't want to get too much int the psychology here, but you are simply repeating a loop in your head based on being afraid and feeling you can't handle something, and that would need to change.
But, when all is said and done, this is also a very common thought process with most people, particularly martial artists, and most commonly with the less experienced or more fearful. So don't take anything I've said too harshly, it's all been quite gentle, really. And it's all just part of the growth process.