An interesting solution to the problem I mentioned the other day:
Tormented by the demon of lust, Moses [the Black of Ethiopia, a former robber who had repented and become a monk] confessed to [Saint] Isidore, his spiritual father, who gave him counsel to increase his fasting, and even when eating to avoid satisfying his appetite. When this regimen did not help, he was counseled to keep all-night vigil and to pray standing. Then he also began the practice of bringing water to the elderly monks from a distant well, all night long. After six years of terrible struggles, St. Isidore miraculously healed him of lustful thoughts, fantasies and dreams perpetrated by his demon. (The Prologue of Ohrid, Volume II, p. 235)
Wow! That's an intimidating solution to the problem.