While there are no true competitors to the Porsche 911 in terms of its unique combination of rear-engine, rear-drive, high-performance luxury, there are several cars which play in the same general space, including the 2012 Chevrolet Corvette Z06 and ZR1, the 2012 BMW 650i (and M6, when it arrives), the 2012 Jaguar XKR, and the 2012 Nissan GT-R.
While the BMW 6-Series and the Jaguar XK offer markedly less performance in a more muted package, they are still very fast vehicles in their own right.
The BMW errs farther on the side of luxury and substantiality, sacrificing nimbleness and handling in return.
The XKR balances closer to the performance end of the spectrum, but its aging platform and styling put it a step behind the 911 on both luxury and agility.
Nissan's GT-R is perhaps the most direct competitor, though it costs a bit less and offers a bit more performance.
The GT-R is also notoriously expensive to maintain, not as well finished or outfitted inside, and appeals to a very different aesthetic than the sleek and curvaceous 911.
It's a tremendously fast and capable car, however, and well worth a look if you're in the market.
Finally, the Chevrolet Corvettes.
The Z06 is a 505-horsepower, naturally-aspirated, front-engine/rear-drive beast of a sports car, delivering supercar performance for less cost than the Porsche.
At the same time, it delivers less luxury and refinement, as well as a touch less daily praciicality, though not much less.
The ZR1 turns the wick up to 638 horsepower thanks to a supercharger, yet costs just about the same as a well-equipped 2012 Carrera S.
In the end, however, the Corvettes make clear sacrifices to build quality and materials in favor of performance.