As I was reading some of my usual blogs, I came across a link in a post from John Nack's blog to a tutorial about how to make your car look like one of the Cars cars. It's actually not that hard to do. There's a certain amount of selections and masking and matching colors but it's not too bad.
I found a picture of a car similar to mine, used Lightning McQueen's mouth, Sally's eyes, some Photoshop magic and voila! I didn't spend a whole lot of time with it, so there are spots here and there that I could do a better job with next time - maybe add an effect to the surface of the original car to help it blend better and look more like a cartoon, too - but it's a fun little project.