In the context of cars, a "wild card" can refer to:

1. Unconventional or unusual design features.
2. Unexpected performance or handling capabilities.
3. Unique or experimental technologies.
4. Limited-edition or specialty models.
5. Cars with a reputation for being unpredictable or temperamental.

Examples of wild card cars include:

1. Bugatti Veyron - Extreme performance and design.
2. Tesla Cybertruck - Futuristic design and electric powertrain.
3. Ariel Atom - Minimalist, high-performance roadster.
4. Nissan GT-R - High-performance capabilities in a practical package.
5. Pontiac Aztek - Unconventional design and features.