Finally, a really worthwhile use for cellular technology. Global Pet Finder is essentially LoJack for dogs in case they get lost. If your dog wanders out of the area, it will transmit its location every minute to your cell phone, PDA, or pager. You can also check your dog's location on their website. Alternatively, you can manually locate your dog by dialing "FOUND" from your cellphone.

One other really cool feature is a temperature sensor, which will cause the unit to transmit a warning if the air temperature gets dangerously high or low.

GlobalPetFinder
$350 plus $35 activation fee and $18 to $20 monthly service fee

Manufactured by and available from Global Pet Finder
 Also from Amazon