<< No, because those things actually help to increase the performance of your computer. The big thing about "ricing" your car, is adding all these stickers, huge exhaust pipe, etc. because you think you're increasing your performance, but you're not. >>
An exhaust system does increase performance. While the aesthetic aspect of "ricing" a car up do not necessarily increase performance, it does increase its aesthetic appeal to a small portion of the population, not me however. Your argument stating that the people putting stickers on their car are doing because they think it increases performance is simply stupid. It is about aesthetics. The same reason people put AMD stickers or intel stickers on their computer case. It does not increase performance, but does make the object the sticker is adorned on more aesthetically pleasing in the eye of the owner. The stickers are an advertising vehicle for companies, as some actually do sponsor some of these "rice" cars.
Painting it black increases performance? Putting it in a clear case increases performance? No. Overclocking is akin to people trying to get more performance out of their vehicles. Decorating the case/car are no different.