Bugatti Veyron 16.4 Grand Sport. Estimated 2013 base price - $2.25 million U.S. (FRANCOIS MORI/AP Photo)
Lamborghini Reventon - announced in 2007, the limited-production Reventon was the most expensive Lamborghini ever built. Base price was $2-million (U.S.) Only 20 were built. (Lamborghini)
Pagani Zonda. Because each car is custom built, prices vary. Some have sold for over $1.6 million U.S. (Pagani Automobili)
Koenigsegg Agera R - made in Sweden. Base price - $1.6 million (U.S.) (Valentin Flauraud/REUTERS)
Aston Martin One-77. Only 77 were built, and no two are identical. Prices range from $1.5- to $2-million (U.S.) (David Shepherd, Peter Cheney)
Maybach Landaulet - $1.38 million (U.S.) (Daimler)
Hennessey Venom GT. Base price - $1.1 million (U.S.) Owners include Aerosmith frontman Steve Tyler. (Hennessy)
Rolls-Royce Phantom. Base price - $398,470 (U.S.) (Rolls-Royce)