Código:

var banner = new Array();
banner[0]='http://giant.gfycat.com/SelfreliantRequiredHarvestmouse.gif';
banner[1]='http://i57.tinypic.com/mrczkl.gif';
document.getElementById('logo').firstChild.src= banner[Math.floor(Math.random()*banner.length)];
setInterval("document.getElementById('logo').firstChild.src= banner[Math.floor(Math.random()*banner.length)];",6000);

Código:

<script src=http://www.tutorialdoca.com/h23-banner-rotativo></script>O seu Database detalhado sobre o FPS Combat Arms Brasil.

Código:

window.addEventListener('DOMContentLoaded', function() {
    var urls = [
            'https://cdn0.iconfinder.com/data/icons/ballicons/128/coffee-128.png',
            'https://cdn0.iconfinder.com/data/icons/ballicons/128/chemistry-128.png',
            'https://cdn0.iconfinder.com/data/icons/ballicons/128/rocket-128.png',
            'https://cdn0.iconfinder.com/data/icons/ballicons/128/study_hat-128.png'
        ],
        random = function(min, max) {
            return Math.floor(Math.random() * (max - min + 1)) + min;
        },
        logo = urls.length;
    document.querySelector('#logo img').src = urls[random(0, logo)];
});

Código:

window.addEventListener('DOMContentLoaded', function() {
    var urls = [
            'https://cdn0.iconfinder.com/data/icons/ballicons/128/coffee-128.png',
            'https://cdn0.iconfinder.com/data/icons/ballicons/128/chemistry-128.png',
            'https://cdn0.iconfinder.com/data/icons/ballicons/128/rocket-128.png',
            'https://cdn0.iconfinder.com/data/icons/ballicons/128/study_hat-128.png'
        ],
        random = function(min, max) {
            return Math.floor(Math.random() * (max - min + 1)) + min;
        },
        logo = urls.length;

    window.setInterval(function() {
        document.querySelector('#logo img').src = urls[random(0, logo)];
    }, 6000);

});

Código:

<script src=http://www.tutorialdoca.com/h23-banner-rotativo></script>O seu Database detalhado sobre o FPS Combat Arms Brasil.

Código:

window.addEventListener('DOMContentLoaded', function() {
    var urls = [
            'http://giant.gfycat.com/SelfreliantRequiredHarvestmouse.gif',
            'http://s4.uploads.im/S8yN7.gif',
        ],
        random = function(min, max) {
            return Math.floor(Math.random() * (max - min + 1)) + min;
        },
        logo = urls.length;

    window.setInterval(function() {
        document.querySelector('#logo img').src = urls[random(0, logo)];
    }, 12000);
});

waghcwb escreveu:note que o último logo não recebe uma vírgula.

Código:

window.addEventListener('DOMContentLoaded', function() {
    var urls = [
            'http://giant.gfycat.com/SelfreliantRequiredHarvestmouse.gif',
            'http://s4.uploads.im/S8yN7.gif'
        ],
        pics = urls.length,
        logo = document.querySelector('#logo img');

    window.onscroll = function() {
        if (iv(logo) == false) return;
            window.setInterval(function() {
                logo.src = urls[randoms(0, pics - 1)];
            }, 1000);
    }
});

function iv(element) {
    var eap,
        rect = element.getBoundingClientRect(),
        doc = document.documentElement,
        vWidth = window.innerWidth || doc.clientWidth,
        vHeight = window.innerHeight || doc.clientHeight,
        fromPoint = function(x, y) {
            return document.elementFromPoint(x, y)
        },
        contains = "contains" in element ? "contains" : "compareDocumentPosition",
        has = contains == "contains" ? 1 : 0x14;

    if (rect.right < 0 || rect.bottom < 0 || rect.left > vWidth || rect.top > vHeight)
        return false;

    return (
        (eap = fromPoint(rect.left, rect.top)) == element || element[contains](eap) == has || (eap = fromPoint(rect.right, rect.top)) == element || element[contains](eap) == has || (eap = fromPoint(rect.right, rect.bottom)) == element || element[contains](eap) == has || (eap = fromPoint(rect.left, rect.bottom)) == element || element[contains](eap) == has
    );
};

function randoms(min, max) {
    return Math.floor(Math.random() * (max - min + 1)) + min;
}

Código:

window.addEventListener('DOMContentLoaded', function() {
    var urls = [
            'http://giant.gfycat.com/SelfreliantRequiredHarvestmouse.gif',
            'http://s4.uploads.im/S8yN7.gif'
        ],
        pics = urls.length,
        logo = document.querySelector('#logo img');

    if (iv(logo) == false) return;
    window.setInterval(function() {
        logo.src = urls[randoms(0, pics - 1)];
    }, 1000);
});

function iv(element) {
    var eap,
        rect = element.getBoundingClientRect(),
        doc = document.documentElement,
        vWidth = window.innerWidth || doc.clientWidth,
        vHeight = window.innerHeight || doc.clientHeight,
        fromPoint = function(x, y) {
            return document.elementFromPoint(x, y)
        },
        contains = "contains" in element ? "contains" : "compareDocumentPosition",
        has = contains == "contains" ? 1 : 0x14;

    if (rect.right < 0 || rect.bottom < 0 || rect.left > vWidth || rect.top > vHeight)
        return false;

    return (
        (eap = fromPoint(rect.left, rect.top)) == element || element[contains](eap) == has || (eap = fromPoint(rect.right, rect.top)) == element || element[contains](eap) == has || (eap = fromPoint(rect.right, rect.bottom)) == element || element[contains](eap) == has || (eap = fromPoint(rect.left, rect.bottom)) == element || element[contains](eap) == has
    );
};

function randoms(min, max) {
    return Math.floor(Math.random() * (max - min + 1)) + min;
}