How many witches?
A fascinating debate is running on the Women's Studies list about witches - specifically the number executed in the last millennia in Europe, with estimates running from 20,000 to 200,000 - a figure of 9 million that has been floating round has been dismissed (it seems to me sensibly enough) as ridiculous.
One of the most debated books has been Robin Briggs. Witches and Neighbors: the Social and Cultural Context of European Witchcraft. For balance a broadly positive review and mainly negative one.
We were also directed to an online edition (with explanation) of the Malleus Maleficarum.
It is not a subject I've got into myself - it seems like such well-trodden ground.