Some of the unusual ones in my tree have already been mentioned here:
Girls - Loveday, Thirza Merhalia, Charity, Bartha, Agese, Robina, Petronella, Lavinia, Christian, Tamar, and my very favourite - Sybella. There is also an Eliessbeth and a Julchen, but they were German so probably not that unusual.
Boys - Emmanuel, Cornelius, Elisha, Jabez, Job, Hay, Michaud (French). My husband's ggrandfather apparently had a sibling called Seppelt.
Unfortunately none of these people are in my Smith line. No, they're all Johns and Freds and Bills and Charlies. Impossible!!