Lizzie Whitlock (1853-1899) was apparently the original fat circus lady. I can't find any pictures of her online, but her grave is now an offbeat tourist attraction in rural Michigan, Batavia Cemetery to be exact.
Findagrave says: "She joined the circus at age 14, travelled with many outfits including Barnum and Bailey's. When she died she weighed 650. The windows were removed from the home to remove her body. She was married 3 times and had four children." I'll bet her truth was a lot more complicated than that.
Anyway, a group of us fatties paid a visit in January 2007, and left her some cupcakes.