The 2006 model year marked the debut of the Infiniti M45 sedan. Let’s recap some of the highlights: technology, technology, and technology. Some of the gadgetry makes sense, and some of the wizardry falls a bit short. On the upside, the rear wheel drive M45 Sports Sedan has active rear steer. It’s a system that adjusts the geometry – essentially moving both rear lower links of the rear suspension based on steering input and vehicle speed. That’s a neat feat. On the opposite side, the intelligent key with push button start has a certain cool factor, but it’s so easy to forget the fob and leave the car running. And guess what? It’s possible to drive the car away whether or not the key fob is in-vehicle so long as the vehicle ignition has been engaged. (This was tested. After handing the key-fob to a passenger, who exited the vehicle and stood curbside, the vehicle was driven away.) For the 2007 model year, the M45 Sport Sedan adds new option packages, such as a $2,500 advanced technology package that includes a lane departure warning audible (which can be disengaged by a lower dashboard switch) and intelligent cruise control (with a live view of what’s behind the vehicle). The sports sedan, which has 19-inch tires and wheels, employs a 4.5-liter V8 that produces 325 horsepower and 336 pounds-feet of peak torque. (That same powerplant is also used in the Infiniti FX 45.) Mile per gallon counts on the M45 Sport Sedan with V8 and 5-speed automatic transmission are 17 city and 23 highway, while the MSRP is $50,550.