I 'm going to do it in few hours ^^
It's easy just create Array for setup colors and choose random in Array.

hi ben, that would be great!! I did an array, but don't have any idea how to continue..

here it is : colorz are in rgb 1 is for 255 ... 0.5 for 127 // black is 1,1,1

var sel = activeDocument.getSelectedItems();
var colorz = new Array();
colorz[0]=new RGBColor(0.5,0.5,0.5);
colorz[1]=new RGBColor(1,0,0);
colorz[2]=new RGBColor(0,1,0);
colorz[3]=new RGBColor(0,0,1);
for (var i = 0; i < sel.length; i++) {
art = sel[i];
if (art instanceof Path) {
var color = colorz[Math.round(Math.random() * (colorz.length-1))];
if (art.style.stroke.color != null) art.style.stroke.color = color;
if (art.style.fill.color != null) art.style.fill.color = color;
}
}

thank you about million times!! I owe you a beer :) - thanks!

I ran the script and it works well. I have a request/idea to expand it, though. (I understand the logic, but don't know the coding language—anyone want to help?)

Can a menu be called that gives you 6 input fields: high and low R,G, and B value (range: 0-1, or maybe let the user input the exact 0-255 RGB range then divide by 255?) and a value for array element number (2-max)? You could randomize the range of the RBG colors and use that to populate a user defined number of array elements. Sounds easy enough, right?

Alternatively, you could do a center point value and a variance value (in % maybe?) to define the random range of color. Values (in percentage) for a CMYK set would be nice too.

yeah, it was the first idea I had (although I didn't expect someone will write it, I am ok with this simple script written by Ben). But maybe there's one problem with it: the number of colors cannot be controlled in any way. I think the better idea is to let the script choose colors randomly from the Swatches pallete, then you can control appearance and number. Also gradients or patterns if I want to. I'm gonna try to write it, at least I have a goal to start learning JavaScript...

Yeah, good idea to use the swatches palette for that.
I'm not sure if Gradients and Patterns will work yet though..
If you need any help, feel free to post your questions here and we'll help you along with your code.