On Tue, 18 Dec 2012 17:19:46 +0000, Andrew May wrote:

One feels that this is the sort of thing that the should be an app for
on a smartphone. Probably something simple like if it can see your WiFi
then divert the phone to home. Remove the diversion when it can no
longer see your WiFi. Voila.

It would be the sort of itch I'd scratch to learn how to program a
'droid. But as I don't have a smartphone I don't have the itch...

Wouldn't be surprised if there isn't something out there already, not
having a smartphone I haven't looked.

--
Cheers
Dave.