We just started carrying these at PetSmart, it looks kind of neat. It's not like a typical ID tag in which it's engraved. It's got the website address, a 1-800 # and a serial # on it. If someone finds your dog they can either go online and get your info, or call the phone # on the tag and get your info that way.
Also, if your dog is lost you can log onto the site and send out a "broadcast" to shelters in a 50 mile radius. You can upload photos, insurance info, and other identifying information on the website, and that's sent in the "broadcast."
It looked pretty neat. Free for the first year, and $6.95 for every year after.
Welcome to IDTag!