I can't help about gas milage, but I just saw that Saturn is releasing a roadster similar to the Pontiac Solstice that I fell in love with and posted a thread about. My Tivo downloaded an ad for it, they are calling it the Saturn Sky..
I figure it probably will be priced about the same, so now I have two cars to look forward to.
As far as Hybrids go, the Honda hybrids are cheaper but they don't look as nice as one's from Toyota, but they get about the same gas milage.