It is RPGNow/DriveThruRPG/OneBookshelf's annual GMs Day sale and there is a ton of books on sale.
Including Sisters of the Aquarian Order.
In fact the Sisters seem to be in very good company right now.
#7 on the GMs Day sales. You can pick it up along with White Star.
I am taking this time to comb through my wish list and grab those books I have been wanting for a while.