I've found an interesting article about exotic police vehicles from Autobild. (Click "Zur Bildergalerie" to watch pictures)
There you got the best cop's weapons from all the world. From Korean police-Diablo to some insane Texan interceptors.. From New-York's pizza-police-mobile (LOL) to VW Transporter... Especially astonished me Dubai's police department that keeps Aventador, SLS, Ferrari FF, Camaro SS (that seems to be some cheap Caprice in line with these exotics) And one of $1.8 Aston Martin One-77! Watch and enjoy! ;)
Shamefully, I had no experience meeting any spectacular police car... My local police department provides only crap-cars... If you are lucky, you'll see some old BMW 5-Series, or Opel Omega... But, once I had a chance to see a police Mercury! Even that was piece of crap, but amazed me because cars of such American brands are Extremely unpopular in my country, and I met one as a police vehicle, pretty much unexpectable! I would be less amused watching police Bentley.