I don't hypermile necessarily, but I went to fill up recently after fixing my odometer and this is the result I got.
Which comes out to 23.6 MPG in a V8 Mustang.
It's just shy of the estimated highway mileage, and most of my miles are driven in that fashion. I'll try to be a little more careful in the next couple of tanks to see if I can't hit 25 MPG at least once!