The peak (in my experience) was the late 80's, early 90's. They weren't really considered geeks so much back then, but a least half of our IT group(s) were female. It seems now like they've shifted to other fields such as accounting, banking, advertising, medical, etc.
What does an agnostic, dyslexic, insomniac do? He lies awake at night wondering if there's a dog.