Yay for PHP people! I felt like making a method though more fun than a function. This works almost exactly the function for PHP except it's for JavaScript and it's a method.

Array.prototype.array_random = function(){
var devarr = new Array();
var addarr = new Array();
devarr = devarr.concat(this);
if(this.length == 0){
return false;
} else if(this.length == 1){
return devarr;
}
if(arguments[0]){
arguments[0] = parseInt(arguments[0]);
for(a=0;a<arguments[0];a++){
var rannum = Math.floor(Math.random() * devarr.length);
addarr.push(devarr[rannum]);
devarr.splice(rannum,1);
}} else {
var rannum = Math.floor(Math.random() * devarr.length);
addarr.push(devarr[rannum]);
}
return addarr;
}

An example of its use:

var patches = new Array('dog','cat','monster','cowboy');
alert(patches.array_random(2));

That would return three random elements of that array. There is one parameter and that is the number of elements you want to pull randomly from the array. Leaving it blank, will return one element.