The Bugatti Veyron top speed key is another one lacking any hitch-tech features. But, it makes our list for serving a very specific function.

The top speed key is aptly named because you have to put it in a slot to the left of the driver's seat to reach the Veyron's top speed of a whopping 253 mph. Without the key, you can still get the car up to a sweet 213 mph.

But toggling the top speed key will make the car's rear spoilers retract and the front diffusers shut so it can that extra 50 mph.