Among the car tuning community, the term "ricer" is used to describe a vehicle that, quite simply, looks fast, but doesn't drive fast. It also may refer to the owners of such cars. Instead of upgrading the actual performance of the automobile, these people put money and work into just giving the superficial impression of a high performance vehicle, because that is cheaper or easier to do.
Most modifications ricers make are visual, such as tinted windows, chrome rims, larger wheels, euro lights, non-functional cold air intakes, stickers and decals. They may also add a giant sound system which makes the car "louder", but actually adds weight, thus in fact making the car slower. Bodykits, spoilers, and racing exhausts are especially popular among ricers since they look impressive, however they don't help with speed or handling significantly unless the car is high performance already. Which a ricer, per definition, is not.
There are certain car models notorious for being turned into a ricer, most notably import cars, among these most popularly Japanese brands, among these most prominently Honda models, and again, among these, most typically Honda Civics. This is because the models are cheap, but easy to turn into "looking fast," since the number of tuning parts available for Japanese import cars is legendary.