What are some related poems, short stories, or graphics related to "The Bet?"

This is a challenging question. It is hard to think of any literary works that are directly related to or derived from "The Bet." But there are numerous works that have some resemblance to one or more of the themes in Chekhov's story. Those themes are solitude, study, and murder. 

In the first place, there are the four gospels in the New Testament: Matthew, Mark, Luke and John. The lawyer read many books during his period of captivity, but eventually he seems to have focused his full attention on the Christian message contained in those four books.

Then after the tenth year, the prisoner sat immovably at the table and read nothing but the Gospel. It seemed strange to the banker that a man who in four years had mastered six hundred learned volumes should waste nearly a year over one thin book easy of comprehension. 

The implication is that after the prisoner had looked for what he wanted to find out in six hundred volumes, he found it in the Bible. The best translation of the four gospels is still the King James Version because of its beautiful language.

Robinson Crusoe by Daniel Defoe is related to "The Bet" in that Crusoe was in a sort of solitary confinement on a deserted island for many years and became a philosopher as a result of the experience.

"The Prisoner of Chillon," a beautiful poem by Lord Byron, is about a man who was kept a prisoner in a dungeon for many years. During a large part of his captivity he was alone because the relatives he had been imprisoned with died off and left him in effect in solitary confinement. He too became a philosopher in his confinement.

The Count of Monte Cristo by Alexandre Dumas and Auguste Maquet is about a man who spends a great many years in solitary confinement in the Chateau D'If on an island in the Mediterranean.

Poems about solitude include Edgar Allan Poe's "Alone" and William Butler Yeats' "The Lake Isle of Innisfree." Yeats said that his poem was inspired by his reading of Henry David Thoreau's book Walden. Thoreau loved solitude and read a great many profound books himself. Like the lawyer in Chekhov's story "The Bet," Thoreau was trying to solve the mystery of human existence. In the chapter titled "Solitude" in Walden he wrote:

To be in company, even with the best, is soon wearisome and dissipating. I love to be alone. I never found the companion that was so companionable as solitude. 

In a little-known short story by Jack London titled "The Star Rover," a prisoner in solitary confinement who undergoes frequent torture over the years learns to use his mind as an escape from his misery. He experiences past lives and other fascinating psychological phenomena.

In Leo Tolstoy's short story "God Sees the Truth But Waits," a man is wrongfully imprisoned for murder and spends many years in prison but develops religious enlightenment which gives him wisdom, patience and solace.

There must be many other literary works about the themes of solitude and religious enlightenment. A story that concerns a man like Chekhov's banker who plans to commit a murder to get out of paying a legitimate debt is the Sherlock Holmes classic "The Adventure of the Speckled Band." There are other Sherlock Holmes stories in which the villain's motive is to get out of parting with money.