http://puu.sh/lOui Collision of player object (named Player) with powerup block (named Powerup). Both have Box Colliders.

Code in Player script:
function OnCollisionEnter (myCollision : Collision)
{
	if (myCollision.gameObject.name == "Powerup")
	{
		powerLevel += 1;
		Destroy(myCollision.gameObject);
	}
}

Do they need rigidbodies or something?