Any parents here have an "internal timer" that automatically goes off roughly every 1-2 min. when your doing something, and also watching your kids? By that I mean like your working in the yard, the kids are playing out back...suddenly its quieter than normal, your "two min timer" goes off and you think "hey, its quieter than normal..." then you go check on the kids...I think its a natural part of parental nature in most parents (I say "most" because a few crack heads are probably wondering what day they changed the diapers on their kids last...)
Our 6 yr.old likes to visit his friend down the street, about 4 houses away. We let him have his independence and ride his bike over there..but he must call us once he arrives..just a safety thing...I'd still have him do this even if we had a GPS chip on him...though the "chip" sounds pretty bizarre, I'd have to wait and see how this is implanted, tested...maybe in a few years when its just an atomized chip injected via a shot or something, dissolvable at a certain age (shrugs)