Apply force to a specific point on a rigid body

Question

In unity I have a rigid body object and would like to apply force to a specific point. For example say I had a cube, I want to hit just the top right corner so it spins as a result. One idea I had considered is spawn a small sphere and fire it at it, then destroy the sphere. But is there a way to just apply the force?

Answer 1

http://docs.unity3d.com/Documentation/ScriptReference/Rigidbody.AddForceAtPosition.html

void ApplyForce(Rigidbody body) {
    Vector3 direction = body.transform.position - transform.position;
    body.AddForceAtPosition(direction.normalized, transform.position);
}