If you are tired of all the oxidized and faded black and gray trim on your car don't despair. There is an awesome product out there that can bring it back to life - for a fraction of the price if you were to replace all of the faded bits. The product is called Mothers Back-to-Black and it is available at most automotive distributor places.
This is what the bottle looks like. All you need now is two soft towels and a couple of hours (if you plan to do your entire car). The job itself is easy, just repetative and takes time.
This is what my trim looked like before I began to work on it. Hard to see right now, but the condition of it isn't the best (also not the worst I've seen out there). In person it looked dark gray, and in my books it just wasn't up to par.
To apply just put a fair amount on one of the cloths and massage it into the trim/rubber (don't be afraid to get some on paint - it comes off fairly easy after). After working some of the compound in let it dry for about 5 minutes. After it dries, take the second cloth and polish the trim to a nice shine. Repeat this process until the trim or seals that you are working on returns back to its former glory! This is what the finished product should look like: