The velocity relative to the rigidbody at the point relativePoint.

GetRelativePointVelocity will take the angularVelocity of the rigidbody into account when calculating the velocity.

	// 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

public class Example(MonoBehaviour):

	public point as Vector3

	public velocity as Vector3

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