Dickens was preoccupied with looking in the mirror and combing his hair - he did it hundreds of times a day. He rearranged furniture in his home - if it wasn't in the exact "correct" position, he couldn't concentrate. Obsessed with magnetic fields, Dickens made sure that every bed he slept in was aligned north-south. He had to touch certain objects three times for luck. He was obsessed with the need for tidiness, often cleaning other homes as well as his own.
Dickens suffered from epilepsy and made some of his characters - like Oliver Twist's brother - epileptics. Modern doctors are amazed at the medical accuracy of his descriptions of this malady.
Hans Christian Andersen was Dicken's close friend and mutual influence. Andersen even dedicated his book Poet's Day Dream to Dickens in 1853. But this didn't stop Dickens from letting Andersen know when he'd overstayed his welcome at Dickens's home. He printed a sign and left it on Andersen's mirror in the guest room. It read: "Hans Andersen slept in this room for five weeks, which seemed to the family like AGES."
(the above from Uncle John's Fast-Acting Long Lasting Bathroom Reader, cited in Neatorama)