function banner() {
};

banner = new banner();
number = 0;

// bannerArray
banner[number++] = "<a href='marathi_mobile_wallpapers.htm'><img border='0' src='random-link/mobile_wallpapers_marathi3.jpg'></a>"
banner[number++] = "<a href='marathi_vidamban.htm'><img border='0' src='random-link/banner_marathi_vidamban.gif'></a>"
banner[number++] = "<a href='marathi_mobile_wallpapers.htm'><img border='0' src='random-link/mobile-wallpaper.gif'></a>"
banner[number++] = "<a href='downloads.htm'><img border='0' src='random-link/wallpaper_india1.jpg'></a>"
// keep adding items here...

increment = Math.floor(Math.random() * number);

document.write(banner[increment]);