You see a vanity plate on the car ahead of you. Perhaps it's on a Ford Mustang, a Volkswagen New Beetle or a Mini Cooper— cars that just beg for vanity plates. You read it over and over, wracking your brain to decipher its meaning, wondering if you're missing a good joke.
It helps if you know "the code." Like the abbreviations and symbols used in e-mail and instant messaging ("BTW," "LOL," "TTYL"), there is a shorthand for vanity plates (also known as "personalized license plates" or "custom plates"). Fortunately, there are dictionaries that will tell you, for example, that "U4IC" means "euphoric," and "6S" means "success."
http://www.baac.net/michael/plates/index.html
http://www.vanity-plates.com/
THIS ONE HAS PICTURES OF VANITY PLATES AT BOTTOM -
http://pages.prodigy.net/pizzabagel/VanityPlates.htm