Renderer.enabled

var enabled : boolean

Description

Makes the rendered 3D object visible if enabled.

JavaScript
    // make the object invisible
renderer.enabled = false;

Another example:
JavaScript
    // Toggle the Object's visibility each second.
// make the object visible
renderer.enabled = true;
function Update () {
// Find out whether current second is odd or even
var seconds : int = Time.time;
var oddeven = (seconds % 2) == 0;
// Enable renderer accordingly
renderer.enabled = oddeven;
}