Collider.enabled

Enabled Colliders will collide with other colliders, disabled Colliders won't.

This is shown as the small checkbox in the inspector of the Colliders.

JavaScript

collider.enabled = false;

using UnityEngine;
using System.Collections;

public class example : MonoBehaviour {
    void Example() {
        collider.enabled = false;
    }
}

import UnityEngine
import System.Collections

class example(MonoBehaviour):

    def Example():
        collider.enabled = false