Buddhist monks uses meditation to free themselves from the everyday struggles... through meditation they are able to free their thoughts toward enlightenment... one step closer to heaven.... it was rumored that one monk meditated over a year, everyone thought he was dead due to no pulse, but his body did not decay but minor fungus on skin.
I've heard all sorts of stories about psychic powers reached in Buddhist meditation. In Tibetan mediation the Guru. Master or Teachers powers are welcomed and used to inspire students to build faith and inspire them to continue their practice. I know this is basically the same in Mahayana Buddhism, you know Zen, Pure Land, Ch'an to name a few. But all my teachers have told me the psychic powers are not worth the distraction if one hasn't achieved enlightenment first. So stay focused and keep on meditating no matter what happens ;-) hahaha pay no mind to all the pretty lights and bliss :p
My Theravada mediation teachers told me to just watch and don't do anything. Psychic powers pass away like everything else in this world.
Monks go away from the world so they won't be tempted, it is easier to focus on study and mediation that way. However the monks I know are so busy with temple duties and study, they don't have much time to meditate ;-)