Unveiled at the Paris show last year, the Citroen C-Metisse Concept is another attempt to create a diesel hybrid car. What’s so exciting about that? well this particular vehicle can operate in a Zero Emission mode, an all electric mode perfect for city cruising, while giving you access to the power of the diesel engine when needed in the motorway. While not as fast as the Saab, the fact that it has a mixed mode engine puts it just a bit higher in our list.