var y = [25, 8, 7, 41, 22, 11, 2, 1000];

var randomize = function(array) {
    var output = [],
        arrLen = array.length;

    for ( var i = 0; i < array.length; i++ ) {
        output[i] = false;
    }

    var findSpot = function(inputVal){
        var potentialSpot = Math.floor(Math.random()*arrLen);
        if ( !output[potentialSpot] ) {
            output[potentialSpot] = inputVal;
        } else {
            findSpot(inputVal);
        }
    }

    for ( var i = 0; i < array.length; i++ ) {
        findSpot(array[i]);
    }

    return output;
}

randomize(y);