My tank is 55L and it's true what you say about mileage city vs highway with the Honda IMA. The Civic is a flat-out nice car with or without the hybrid.
Prius, that's the first I'm I've ever seen actually pricing. Interesting.
Battery for a 2005 Prius: MSRP $2,985, "Your Price" $2,149 thru OEM Parts Shipping Cart on that site
Of course, that's the battery alone, not the installation labour or any other components. Still, that's the most expensive part and it's less than I thought it would be.