In no particular order:
Jaguar
Mazda
Lexus
Honda
Ferrari
Aston Martin
Lamborghini
Ford
BMW
Land Rover
I picked these on the grounds that I feel they do not make a single bad car in any of their current ranges - I would happily take any car from any of the above manufacturers and be satisfied with it. In many cases, the cars produced by these manufacturers are either the best or competitive with the best of their respective classes (Fiesta, Mazda3, Jaguar XJ, Ford Focus, BMW 5-Series, Range Rover Evoque, for instance). Other criteria include subjective emotional aspects, such as contribution to motorsport (e.g. Honda and Ferrari in F1, Mazda at Le Mans), styling and wow factor (Lamborghini Countach, Aston Martin DB5, and the Lexus LFA particularly stick in my mind), or whether they have been responsible for notable advancements in the car industry (Ford for the Model T, Mustang and Focus, Lexus for the LS, Lamborghini and Ferrari with the Miura and F40, among others). I've also tried to go for a mix of mainstream car manufacturers (Honda, Ford, Mazda), luxury cars, (BMW, Land Rover, Lexus, Jaguar), and top-end stuff (Ferrari, Lamborghini, Aston Martin).