function image() {};
image = new image();
number = 0;
same = "<img align='middle' src='images/";
image[number++] = same + "sideBar_1.gif' />"
image[number++] = same + "sideBar_2.gif' />"
image[number++] = same + "sideBar_3.gif' />"
image[number++] = same + "sideBar_4.gif' />"
image[number++] = same + "sideBar_5.gif' />"
increment = Math.floor(Math.random() * number);
document.write(image[increment]);