We haven't got one for Baldrick the ferret yet, but our two cats have subcutaneous ID microchips implanted. From what I understand, the chip will register a numeric code when a cat, or possibly a ferret, is scanned with the appropriate instrument. This code is the key for that cat's (ferret's) record in a national database. The record contains our name, address, phone number, and other pertinent information, so that if one of them ever gets lost and ends up at the pound, animal control authorities will know how to get hold of us. I wasn't aware of any global positioning system for ferrets OR cats. It would be nice if I could get some sort of handheld device with an indicator that points toward a cleverly-camouflaged ferret. Even better: a fashion ferret pin which sounds an alarm whenever its wearer comes within ambushing distance of a rowdy carpetshark. ["Warning. This is a FerretAlert. There is a risk of serious toe nibbling in Sector 756-G! Please cover your ankles and proceed with caution."] -Brandon + Baldrick (who thinks it might be fun to emit a high-frequency radio signal.) [Posted in FML issue 2439]