what we are seeing in the equity markets today is quite rare. this is what capitulation looks like. this is what happens when folks give up on the market and are so afraid that they want out at any price. one does not see action like this other than at truly historic times, and that what this is.
that doesn't mean you rush in and buy into the teeth of this decline, but the good news is that if you have cash, you are going to have some fantastic bargains to pick from. the bad news is that there is no way to know how long this will continue before we find a low.