Have you seen this?

http://www.testdriveunlimited.com/

What's incredible to me is this:

more than 1000 miles of diverse Hawaiian roads

They actually modeled the entire Hawaiian Island!!! And for you Xbox 360 owners out there:

New Test Drive Unlimited playable demo for the Xbox 360™ video game and entertainment system from Microsoft, via Xbox Live® Marketplace!

With the new demo allowing up to one hour of play in a 60km˛ area of the graphically polished and geographically accurate Hawaiian island of Oahu, players will have time to discover a stunning new house, three delicious new super cars – the Ferrari F430, Ford Mustang GT and AC Cobra – and one brutally powerful motorbike, the Kawasaki Ninja ZX-10R.

Players can choose to accept one of the four new offline challenges, take on either of the two new online challenges with up to eight players racing simultaneously, launch instant challenges against anyone they encounter on the road, or just burn gallons of virtual gasoline tearing around the lush tropical roads in free ride.

Other enhancements include tighter handling, snappy gear changes, customizable speed blur effects, optional in-car camera vibrations, improved lag allowing eight player online races, fully operational vsync, an incredible level of overall graphical polish, and much more.