RaycastHit.point

Description

The impact point in world space where the ray hit the collider.

// Apply a force to a rigidbody in the scene at the point
// where it is clicked.

// The force with which the target is "poked" when hit.
var pokeForce: float;

function Update () {
	if (Input.GetMouseButtonDown(0)) {
		var hit: RaycastHit;
		var ray = Camera.main.ScreenPointToRay(Input.mousePosition);
		
		if (Physics.Raycast(ray, hit))
		{
			if (hit.rigidbody != null)
			{
				hit.rigidbody.AddForceAtPosition(ray.direction * pokeForce, hit.point);
			}
		}
	}
}

using UnityEngine;
using System.Collections;

public class ExampleClass : MonoBehaviour {
    public float pokeForce;
    void Update() {
        if (Input.GetMouseButtonDown(0)) {
            RaycastHit hit;
            Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition);
            if (Physics.Raycast(ray, out hit))
                if (hit.rigidbody != null)
                    hit.rigidbody.AddForceAtPosition(ray.direction * pokeForce, hit.point);
                
            
        }
    }
}

See Also: Physics.Raycast, Physics.Linecast.