"Yes, it's Priora," he told me, "because it's neuter plural. But if you cheated a bit and made the car masculine or feminine - and I do think of cars as female - then it would be Priores. And Priores has nice undertones of grandness - Virgil used it to mean 'forefathers' or 'ancestors.' "
Via Autopia, with a hat tip to David Sturtz.
Photo of 2007 Toyota Prius via Fuelzilla.