The Billiards Holy Light Aiming System is a vague technique that some players use to help them aim their billiard shots and uses the lighting in a room. The Holy Light System by the billiard room’s light reflecting off an object ball. Using this light, and shadows, you can apparently determine the strike area.
Some players claim that the Holy Light System is virtually perfect once you nail it down. Yeah, right. Its WAY over my head! To me, it is the most vague and least-written about aiming systems in pool.
The Billiards Forum has an okay article on the Billiards Holy Light aiming System so that may be a start for you.