Pure dead brilliant

Summary/Review: Time travel, a computer virus that's deadly to humans, and other strange things begin to happen when some would-be witches come to stay with the eccentric Strega-Borgia family. Pandora can't resist the temptation of time travel, Titus picks up a strange--and deadly--computer virus, and it looks like they may have to trade in the family riches for a family curse. Are they falling under the witches' spell? Or is the ghost of the Strega-Borgias' past coming back to haunt them all?