In the UK, the Metropolitan Police teamed up with Caparo to create this concept police car, the Caparo T1 RRV. It can go from 0 to 100 mph in 5 seconds. It sports 575hp at 10,500 rpm from a 3.5L V8 engine and a top speed of 200 mph. It was designed to patrol the M25 Highway.

As a Rapid Response Vehicle, they don't come any more rapid than this.