Just because you're rich and famous, doesn't mean you can buy a good night's sleep. Here are some of the strangest sleeping habits practiced by the world's most famous people:

Tom Cruise sleeps in a sound-proof 'snoratorium' because his snoring is that terrible.  "Whoever uses the snoring room cannot be heard outside the locked door," an alleged visitor to the actor's house told the Daily Mail. "It's very small, comfortable and dark, maybe a former nursery."

Back in in 2007, Mariah Carey told Interview magazine that she surrounds her bed with 20 humidifiers and needs 15 hours of shut-eye per night. Apparently she believes it's good for her vocals.

Eminem puts tin foil on his windows to keep out the light to get better quality sleep. He also likes "white noise playing on the speakers and telly" and finds that this routine helps him sleep better when traveling to different time zones.

Yahoo CEO Marissa Mayer is known to be a workaholic, sometimes clocking as many as 130 hours in a week. She recharges every four months by taking weeklong vacations.

Michael Phelps sleeps in an altitude chamber with air comparable to 8,500 to 9,000 feet. High altitudes have less oxygen, meaning Phelps' body has to work harder to produce more red blood cells and deliver oxygen to his muscles. This helps to increase his performance endurance and prepare himself for competitions at high elevations.

Winston Churchill took a two-hour "siesta" every day at 5 p.m. He first would drink a weak whisky and soda befor etaking a nap for nearly two hours. This allowed him to get one and a half day's worth of work out of every 24 hours. Churchill was also known to be a night owl and would often work through the night. Due to his irregular sleep schedule, he was said to hold War Cabinet meetings in his bath.

According to Lisa Rogak's book "Haunted Heart: The Life and Times of Stephen King," the science fiction writer pillows are all always pointed in a certain direction. Sounds a bit neurotic.

Leonardo da Vinci's sleep schedule included 20-minute naps every four hours. This extreme form of a polyphasic sleep schedule is known as the Uberman sleep cycle. While it may have given the artist/inventor/scientist more awake time during his days, but could have also made it difficult for him to work on long-term projects.

Inventor Nikola Tesla also followed the Uberman sleep cycle, and claimed to never sleep for more than two hours a day. He reportedly once worked for 84 hours in a lab without any rest or sleep.

Emily Brontë walked around in circles until she fell asleep.The 19th century novelist novelist/poet suffered from insomnia, and found that walking around her dining room table helpted to get her sleepy.

Charles Dickens believed that sleeping while facing north helped with his creativity. The writer always kept a navigation compass with him to ensure that he wrote and slept facing this direction. He also supposedly suffered from insomnia.