Here's an interesting, and completely unrelated, article:
New Jack The Ripper Theories Put Sleuths In A Spin
"A handout photograph, taken in the late 1880s and released June 27, 2005, shows Sir John Williams, ancestor of Tony Williams, the author of a new book on Jack the Ripper. In his new book entitled 'Uncle Jack', Williams proposes that Jack the Ripper was his ancestor John Williams, a gynecologist to Queen Victoria's children and the founder of the National Library of Wales.
Williams had set out to explore his family history when he stumbled upon a box of Sir John's personal effects, including a knife, three medical slides and diaries with the 1888 entries ripped out. He discovered that besides his posh Harley Street surgery, Sir John had a clinic in Whitechapel, giving him access to the prostitutes who thronged the area. His medical notes showed he had performed an abortion on the Ripper's first victim, Mary Ann Nichols, in 1885. Williams believes Sir John was enraged by the prostitutes he saw getting pregnant while his own wife was unable to have children and killed them either out of vengeance or to use their organs for researching a cure for infertility. "
I'm not sure we'll ever definitively solve who Jack the Ripper really is. Deep down, I don't think we really want to. I will say that Alan Moore's take on the subject was infinitely better than Michael Caine's. But, as long as the story provides fertile material for writers and amateur sleuths, the story is never going to be put to bed.