So, here is the best invention ever: the in-car sandwich maker. All you need is some salad, some meat (or not, if you are vegetarian) and some bread. And that's it. Turn on the sandwich maker, watch out not to burn yourself (or hit the car in front) and have a nice meal.
P.S.: I was kidding. This is one of the stupidest car gadgets ever. EVER. And if you still want to buy it, you can find it here. Image was taken from here.