// Prints the velocity of the wheel
    var point : Vector3;
    var velocity : Vector3;
    point = transform.InverseTransformPoint(Vector3(0, -.2, 0));
    velocity =  rigidbody.GetPointVelocity(point);
    print(velocity.magnitude);

using UnityEngine;
using System.Collections;

public class example : MonoBehaviour {
    public Vector3 point;
    public Vector3 velocity;
    void Example() {
        point = transform.InverseTransformPoint(new Vector3(0, -0.2F, 0));
        velocity = rigidbody.GetPointVelocity(point);
        print(velocity.magnitude);
    }
}

import UnityEngine
import System.Collections

class example(MonoBehaviour):

    public point as Vector3

    public velocity as Vector3

    def Example():
        point = transform.InverseTransformPoint(Vector3(0, -0.2F, 0))
        velocity = rigidbody.GetPointVelocity(point)
        print(velocity.magnitude)