The other day I was walking through the Novell parking lot and came upon the car pictured at the right. If you look at the larger image, you'll notice that the bumper sticker on the car says "Use my license plate to find me on the Internet" with the large URL: license-plate.com.
Maybe it's just my bias, but I thought that this was a Web site that allowed license plates to be used as general purpose identifiers, allowing license plates to be linked to email and Web addresses. I wasn't sure what use that would be, but I was intrigued.
Turns out that its a car selling site. You register a car you have for sale at the site for free and then people can use your license plate number to find your ad. If you spend $10, they'll send you the bumper stickers and "upgrade" the listing.
There's no indication how many listings the site has. Probably not many. A wildcard search in Utah resulted in 9 listings total--most fairly old. There were zero in California.