Helena Bonham Carter has take on a number of kooky, spooky and downright creepy roles, but certainly Miss Havisham was a part she was meant to play. Though the actress is a bit too young to play it (Dickens has written the character as a woman in her mid-fifties, and HBC is only 45).
Interestingly, it has been suggested that Miss Havisham was not a figment of Dickens's imagination, but was inspired by real events and a real person, though scholars seem to have trouble agreeing who this real person were.
Frederic George Kitton in The Life Of Charles Dickens suggests that Miss Havisham may have been inspired by a lady who lived near Hyde Park and who was burn to death in her house. The other possibility is that the 'real' Miss Havisham was not a lady, but a gentleman by the name of Nathaniel Bentley. Bentley was a wealthy young man whose fiancee died on the morning of their wedding day after which the wedding banquet was left to rot and the house came into disarray. Bentley himself refused to wash and was dubbed Dirty Dick. There is a pub in London named after him which heavily draws on the legend.
There is another story that says that Miss Hvaisham was inspired by a lady from Australia who wanted to marry beneath her station and whose groom disappeared on the day of the wedding. She stayed in the house and left everything as it was on the day of the wedding, hoping that he would come back.
While Miss Havisham is a wonderful Gothic character, I would hate to think that there was a real person who inspired the story. Such tragedy may be interesting in a work of fiction but it's gut-wrenchingly terrible if happens in real life.