The Insignia Little Buddy is a $US100 child-tracking GPS system. You simply duct tape the Little Buddy to your kid, and you'll never lose the little bugger again (involuntarily).
A web interface positions your various little ones on a map marked with your custom "safety zones". But the most enticing feature, if we're studying the GPS tracking page properly, is that you can assign your children with various barnyard animal iconography. That'll teach little piggy the consequences of being late.