Nice is shocking. About $35 equivalent for the 10 minute ride from the airport to one of the beachfront hotels. My advice - get the bus!
In Delhi last week we hired a cab from our (five star) hotel for six hours for the equivalent of $10. We gave him the equivalent of $16 in the end. Not a bad car, although I wouldn't use it for long journeys - we used luxury SUV's (at suitably high rates) for driving between cities.