Yesterday I saw a Prius with license plate "GRNCAR". Driving between two small towns, this Prius passes me 5 over the limit while I'm 5 under. That car gets about a mile ahead of me at one point. I pull up behind that Prius at the first stop light in the next town, flashing my hi-beams twice, as if to say "Hey, remember me?" I got 47 MPG in those 15 miles. That Prius was lucky to get 40 at the speeds it was going.